The objections of the venerable Edward R. Tufte notwithstanding, slideshow presentations have become an essential part of science. I sit through a great number science talks over the course of any given year. And probably 90% of them are awful. Not in terms of content, necessarily, or delivery; but in terms of ugly, overladen, whatever-the-visual-equivalent-of-tone-deaf-is slides. It doesn’t have to be that way. And frankly, I’ve had enough. So here are some golden rules for slideshow presentations, purely in terms of graphical design (i.e. how to illustrate a good talk, rather than how to give a good talk). Be warned. This is an opinionated rant that has been a long time gestating. But it is also 100% true. First, a disclaimer: If you are a graphic designer, please ignore the following and get on with designing your own beautiful work. But you’re not, are you? You’re a busy scientist trying to put together a talk in a hurry. Me too. Fortunately the nice people who design templates for your slideware package of choice actually do have some understanding of design principles. Yes, even in PowerPoint I daresay (although I switched to Keynote a few years ago, and have recently gone about 18 months without being able to open PowerPoint on my computer without it crashing, so I am perhaps not best placed to say). So, just as you wouldn’t want a designer tinkering with your data – probably best not to insist on putting your own distinctive stamp on their designs. My first rule, then, is:
1. Use design templates. And take them seriously. If a template has room for one image, insert one image. If it has room for three bullet points, that’s how many you should use. The template designers have decided on the optimal size for figures, fonts, etc. that will be appropriate for viewers. Don’t second guess them. My record spot, from a reasonably eminent speaker at a Royal Society discussion meeting, is 24 graphs on one slide. Not good. I have a much lower opinion of his science as a result of that one slide. Why would anyone who has ever seen a scientific talk even think of doing that? It’s 20 years since slides were physical objects that you might wish to use economically. So if you need to use a load more slides to fit in everything you want, then do so. In fact, that’s rule 2:
2. Use as many slides as you need. Given that digital slides are free, I am constantly amazed at how much information people try to cram on each one. There is no penalty for including sufficient slides to allow you to show, say, one figure per slide. But, I hear you say, the figure you want to include is part of a four panel figure from the paper you are promoting. So surely all four parts will have to go on the slide? No. See rule 3…
3. Redraw your figures. The figures that you used in a publication are almost certainly not going to be appropriate for a presentation. Labels will be too small, lines too faint, points invisible (and probably too numerous), and overall the figures will be too complex. So, you should have versions of relevant figures produced specifically for presentations. If, like me, you write little functions to produce all your figures, that’s quite easy – just modify arguments for line thickness, colour, axis labels, etc. If not, redrawing from scratch may seem like a pain, but the likelihood is that you’ll be using these figures multiple times, so the effort will certainly be repaid. If a figure for which you don’t have the raw data is not good enough, consider if you really need to use it. If so – can you digitise it, and so produce your own, prettier version? If so, do. (GraphClick is useful for this, or there’s a digitize packages in R too.)
4. Keep text to a minimum, but no less. I don’t want to read a full set of your notes, in bullet point form, on every slide. Your slides are a communication tool, not an aide memoire. So just write important stuff. But, write it in proper sentences, keeping abbreviations and acronyms to an absolute minimum. (And get your bloody indentations formatted neatly too.)
5. Avoid clutter. Never leave yourself in the position where you have to say, ‘You won’t be able to read this / make this out / discern what I want you to see, but…’ There is one exception, a Joker which can be played at most once per talk, and that is if you wish to illustrate the concept of complexity itself. For instance, you could include a slide of tedious but straightforward algebraic manipulations, to illustrate the tedious (but straightforward) nature of the maths required to reach your result. Or you may wish to stick in a horrendously complex food web network diagram to be accompanied by a wry comment along the lines of ‘as you can see, this system is rather complex…’ (An aside: I included such a diagram in a talk, given to a general audience a few years ago, on communicating complexity, as shorthand for complexity in ecological systems. A few months after, at an ecological conference, I saw a rather high profile marine biologist use the exact same diagram – in fact, 10 of them on a single slide – and proceed to talk as if the audience was able to process them and to discern the salient features. As you can imagine, I was delighted to note this down!)
6. Consistency is more important than specifics. Taste in design is personal. I have my preferred Keynote design templates, others I think are nasty. A lot of PowerPoint templates are pretty ugly, in my opinion. I prefer certain fonts and colour schemes over others. You make your choice (although do familiarise yourself with the basics of colour theory – 5 minutes work, max). Then, whatever your choice, stick to it. All your slides should follow the same scheme. If you’re using a few slides provided by other people, ensure they conform too. (This will probably involve re-drawing them. See rule 3.)
OK, I could go on but that’s probably enough (oh, but, of course – 7. ClipArt. Don’t). Just please, if you want me to concentrate on what you have to say over 5 to 60 minutes, have the courtesy to present a well-designed talk. I won’t respect your science if you don’t. A talk is a story, not a comprehensive CV: give some thought as to what needs to go in, and (most importantly) what can be left out – because the flip side is, if you give a good talk, I will probably go and read your papers, or at least collar you afterwards, and can catch up on details then.
One final point. Stick to all of the rules above, at all times. However, if you should ever see me break any of them, I am doing so knowingly, and that’s fine. Have a beautiful 2012!