Person working on a laptop

#11: How much time is needed to prepare a good scientific presentation?

Do you have to give a scientific presentation at a conference or at your institute, and wonder when you need to start preparing it? How early should you begin to work on your talk to be able to deliver it well? Will one or two days be enough? Should you spend a week or more? Let us give you some guidance on how much time it takes to prepare for five different types of scientific presentations. 

If you ask other colleagues at your institute, you will probably hear all sorts of advice: Some start working very early on their presentation, others a week before and some just the day before. You might also hear that some people don’t prepare their talks at all. So it can sometimes be tricky to get meaningful advice on how much time is really needed for preparing a presentation. 

Years ago, we had a special experience that changed our approach to the time needed for preparing a conference talk. We were on the plane with some colleagues from our institute on our way to a large conference overseas. We all were going to present at the conference, otherwise the institute would not cover the expenses for the journey and the conference. Next to us on the aircraft sat a colleague, a well-known scientist, working on his laptop during the flight. While everybody else was taking a rest on the long journey, he looked very busy with his laptop. We saw he was working with PowerPoint and copying and pasting loads of text and images onto slides that he created on the go. 

After a while we realised what our colleague was working on: It was the slides of the presentation that he was supposed to deliver a day later at the conference. He literally started with the preparation of his talk on the way to the conference. As he told us, he hadn’t done any preparation before. Thus he sat on the plane and was doing the work others, including us, had done before we went on the journey. 

The next day, he presented his on-the-plane-crafted talk. If you had been at this talk you would understand what a jumble it was. It was not one of those presentations that you would remember for long. It just looked like a collection of slides and an accumulation of content bits that were sewn together. Well that’s in fact what he had done on the plane next to us! Have you also observed something similar like we did years ago?

We decided after this lesson on the plane, that whenever we start our journey to a place where we have to present, our presentation is completed and rehearsed BEFORE we get on the plane. But of course, to do so requires some time set aside for the preparation of your talk a good deal in advance! So, if you are also not keen on being under pressure during the journey to complete your presentation and have no time to properly rehearse it, then keep on reading. 

To avoid the stress of preparation at the last-minute, use our following suggestions to help you assess when to start with your preparation and set yourself deadlines for these tasks. For how to deal properly with deadlines and avoid getting down to the wire, best check our post #8 called  “Deadline disaster: Seven easy steps to avoid”

In this post here, we will tell you here how much time you should plan for preparing a scientific presentation. We give you advice for the five types of presentations that you might have to deal with, including conferences. The particular occasion, event, and importance of your upcoming presentation influences how much time you would need to prepare and deliver a talk well. 

Woman sitting on bed and working on a laptop.

1) Ad-hoc presentations 

An ad-hoc presentation is a presentation that was not planned ahead of time before you have to deliver it. What could that be? Imagine a situation like this: Your boss comes in your office, not alone, but with a guest visitor who is at your institute for a day or two. Your boss wants to inform the visitor about the research that’s going on at your institute and introduce a few staff members. Your boss and the visitor come in your office and your boss asks you whether you could briefly tell the visitor something about your research. 

An ad-hoc presentation is a difficult task. There is no time to prepare anything. It often comes as a total surprise. You may think, obviously there is nothing you can do regarding the preparation of an ad-hoc presentation because of the lack of time. Yes and no!

You are right, it’s too late to start preparing it once you’ve been asked to deliver. So, what about preparing yourself for such a situation before it actually happens? Wouldn’t it make a splendid impression on the visitor (and your boss) if you could say that you have something you can show them? Especially if you have actually something that you prepared weeks ago for just such a situation. 

In an ad-hoc presentation, you are not expected to talk for 15 minutes and have a stellar slideshow to go along with it. No, you talk probably for 3-5 minutes and the content is all about what you are doing at the moment. So how can you prepare for this occasion? 

Once you have a quiet afternoon, sit down and block 60 minutes to think about what you could tell in 3-5 minutes about your work so that other people would get an impression of your work. Ideally, you could make a short outline of keywords on one page and have one or two visuals ready to show. You could also create a short slideshow with 3-5 slides where you put the main keywords and visuals, to guide you and to show to somebody. Have the outline always at hand in your drawer or keep the mini-presentation on your laptop or even on your mobile phone so you can always access it. All of this can be done a  good time in advance. It doesn’t take a lot of time to prepare. It is far better to have this mini-presentation than to be totally surprised and unprepared, and we bet it will help you make a good impression! 

2) Last-minute presentations 

A last-minute presentation can be similar to the ad-hoc one but the difference is that there might be a short time to prepare before you actually have to deliver it. Imagine a situation like this: Your institute is hosting a mini-conference with project partners where you inform each other about the ongoing research. A scheduled presenter took ill and suddenly there is one presentation slot left for this afternoon. Your boss or the PI of the project approaches you, and asks whether you could jump in and present in the afternoon. 

This is again a bit a difficult situation. You are probably expected to present for about 10 minutes, so it has to be more substantial. Again, you are expected to present your own work and you don’t need to squeeze it or make it fit into one specific context. At least, you have a bit of time before you present. Your presentation is not immediately taking place, but you might also be expected to fill a whole slot. Thus, it can feel even more stressful to be in such a situation compared to the ad-hoc presentation. You probably have a few hours left to prepare – better than nothing – but if you have nothing to fall back on, the next hours will be stressful (and you probably had planned to spend them differently). 

So how could you prepare for such a presentation? There is a 2-step approach that can help you here: The first step is done in advance of an anticipated request for a last-minute presentation. The second step will fill some of the time from when you receive the request until the talk is to be held. 

  • In step 1: Allocate an afternoon, about 3-4 h to think about the structure and content of a presentation of your research lasting about 10 minutes. Make a short presentation and use 5-8 slides. It can be something linked to the last conference presentation you did, or it can of course also build the skeleton for your next conference presentation. Spend some of the afternoon outlining a meaningful presentation aim and structure, make sure there is a message, create some slides to support you in your delivery and use at least half an hour to rehearse two or three times to see whether it all fits together. Keep this presentation skeleton ready to take it out once you need it. 
  • In step 2: Depending on how much time you can spend on this step before you have to present, you use about 2 h to go through your presentation skeleton and update it, adjust it and rehearse it for the afternoon presentation. 

3) A research seminar presentation

This is typically a 15-20 minutes in-house presentation in front of your colleagues, other staff members, a graduate school meeting etc. You will – more or less – know the audience you are presenting to and you are expected to give a report on your own research progress. It is often followed up with questions and discussion time of about the same length. 

In contrast to the ad-hoc and the last-minute presentation, the research seminar presentation is not a surprise event. You know about it usually a good time in advance, often two weeks or more. This puts you in a better situation, as you can actually plan the use of your time until the delivery.  

If possible, start at least two weeks before the seminar with your preparation. Of course, you are not expected to work the whole next two weeks only on your presentation, but to start so early that it keeps the pressure low and gives you time to reflect on what you want to present: 

  • The first week is used to brainstorm ideas, get them onto paper, and probably make a rough outline of how the talk should be structured. 
  • The second week is used to work more intensely on the content, the message, the slides and any other tools you want to use, as well as rehearsing your talk. 

If complete the whole thing two days before you present, you’ll have enough time to digest the talk and relax. It calms down nerves and gives you time for a last minute rehearsal. 

4) A conference presentation

A conference presentation is similar to the research seminar presentation with a few major differences: The audience is typically larger, you won’t know most of the audience, they won’t know you, and the presentation takes place somewhere else, not at your institute. 

Most likely, you will present for 15 minutes at an international conference and your talk will be held in a parallel session, i.e. one of several sessions running parallel to each other, typically sorted thematically. Audience numbers within the sessions and across sessions can vary. 

Now, most of the conferences are planned long in advance and you have to register your talk approximately 3-9 months prior to the event. Hence, there is ample preparation time – in theory – because many presenters, at the time they register for the conference, do not yet know what they are going to present later. 

In terms of the impact of your presentation, this presentation type is probably the most important one. Therefore, give it enough time for proper preparation. If possible, start 4-6 weeks before the conference to plan and prepare your talk. Get an idea of what you want to present and what you will need to do it well. Then, make sure you still have enough time to get the results, the data, the visuals or anything else you might need. 

Over the next few weeks, make a schedule for where you can work in sessions totalling up to one day per week on the presentation. You will have other duties to do as well and therefore, it might not be possible to spend more time on this task per week. For example, in those 4-5 weeks, you can spend the time like this: 

  • in one session you work on the message and the overall structure, 
  • in one session you develop and outline the content, 
  • in one session you create slides and visuals, 
  • and in one session you think about the way you want to deliver it and rehearse your presentation. 

Have your conference presentation completely prepared at least one week before you go to the conference. This will give you enough time to reflect on it, let it mature and have a few last-minute rehearsals. By the way, some conference organisers even want you to submit your presentation in advance, so it is handy to have it ready a week before. It takes away some of the pressure and stress! 

5) A really important solo presentation

The last presentation type is a special occasion. It can be a short lecture on your research, a talk for your PhD defence, an invited lecture, a keynote presentation at a conference or a presentation during a job talk. What they all have in common is that you will know about these presentations a good time prior to  having to deliver them, only a presentation at a job talk can sometimes be on shorter notice (2-4 weeks before). 

It is also common that the audience comes specifically to hear you to deliver this talk. It is about the content, but also very much about you as a person. You might be the only presenter at the occasion or you will be a presenter with a special, prominent status. The presentation time can also be a bit longer than with the other types listed above: anything between 15-45 minutes. However, these kinds of presentations take place a bit more seldom. 

To deliver well and to avoid any stress in the run-up to the event, start early with the preparation. We recommend to begin at least 6 weeks prior to the talk. Depending on the expected length of the presentation, you will need to spend a bit more time on selecting the right content and organising it to fit the specific purpose. Since most of the solo or keynote presentations are invited talks, the audience, the conference organisers or the selection committee expect you to cover some specific content. 

Hence, in this presentation you will most likely not just tell what you do in your research, but those inviting you for the talk have specific intentions for it. They want to hear something extra and this might require quite some extra work for you to prepare. 

Again, we recommend to complete your preparation about a week before delivery. You might need to spend a bit more time in the run-up period for this presentation than for a regular conference presentation, depending on the length and purpose of the expected talk. In addition to sessions totalling up to one day per week, you might need a week where you work a bit more intensively on the presentation, spending up to two or three days. 

Don’t forget to calculate enough time for the rehearsal of the talk. All eyes of the audience will be on you. You have their full attention and they want to see not only WHAT you present but also HOW you deliver it. Particularly in job talks, this is a vital component of such a presentation. 


A presentation is a unique opportunity to present your work and yourself. Read more about the potential impact of a presentation in our contribution “Why your next presentation matters!” It will give you all the motivation why it might be meaningful to invest a bit more time because a good presentation can be a big win for you. 

How much time YOU effectively invest into preparing your next presentation depends largely on two aspects: 

  1. The occasion and the purpose of the presentation. 
  2. Your personal level of experience with giving presentations. 

Good presentations are not given by magicians or super humans. Behind every good presentation that you see, there was simply a necessary amount of preparation time that went into it. Don’t believe all those who pretend that they never spend much time on preparing a talk, unless of course they indeed deliver poorly and then the presentation is proof of their claim. 

There are only a few speakers around who are gifted enough to deliver well with a tiny amount of preparation. If you do not belong to this group, we highly recommend you to invest time in preparation. Professional presenters make everything look so easy as if it were effortless. Believe us, they invested time to make it look like this and that’s why they are professionals. 

Think about what you want to get out of the presentation and to whom you are presenting, it will help you to determine the amount of time that is needed. Good luck with your next talk!

Relevant resources:  

More information: 

Do you want to present successfully at conferences?
If so, please sign up to receive our free guides.  

© 2019 Tress Academic

Photographs by Alex Kotliarskyi and Victoria Heath at

#ConferencePresentation, #ResearchPresentation, #ConferenceTalk