I spent last week at a conference. As usual, the use of PowerPoint by speakers ranged from excellent to dreadful. I started amusing myself by writing down the things people did wrong with PowerPoint, and that has led to a set of suggestions for people who aspire to getting their message across effectively.
The obvious things
On each slide, include only a few points - no more than about six, and fewer is better. It is OK to have only one point on a slide.
For each bullet point, include only a word or a few words, not a sentence. The last thing you want is to have to read out what's on the screen, but if it's a sentence, you more or less have to. If you have a sentence on the screen but then don't read it out, the audience will be reading it while you're saying something else. Or they'll be scanning through the bullet points trying to work out which one you're talking about, rather than listening to you.
These days, if you add more and more text to a slide, PowerPoint reduces the font size to make it fit. Don't fall into that trap. If PowerPoint has had to reduce the font size, you've got too much text or too many points on the screen.
Never move the boundaries of the text box to fit more text in. Keep reasonable sized boundaries around the text of your slide.
Use pictures where possible. It's good to use pictures instead of text to prompt you, if possible. At least use pictures to illustrate or illuminate the point you are making. Most people take in pictures more easily than text. Personally, my natural inclination is to rely mainly on text, but I try to go back and insert pictures, or replace text with pictures, once I have a draft PPT file. Think carefully about which pictures will best illustrate the point you are making.
Keep graphs and tables simple. This is one that many people violate, sometimes to a ludicrous extent. Putting large tables on a slide is just dumb. The audience will spend the whole time trying to work out which numbers you are referring to. Sometimes people put up a large table and then use colours or a box to highlight the few numbers they actually talk about. This is better than not highlighting them, but why not just leave out all of the numbers you are not going to talk about? A table with six to eight numbers in it is good.
Bar graphs are easiest to take in, or use simple line diagrams. Don't have more than two data series in a graph if possible.
Make sure the text on the axes of graphs is easily big enough to read. Whenever a new graph comes up, start by describing what is on the axes, and then briefly describing the content of the graph, before you get into discussing its implications. People need help to tune into the graph. The same is true of tables, more or less.
Only have one graph or table on the screen. If you want people to compare two data series, put them in the same graph or table.
PowerPoint has the ability to automatically change the format of text and bullets depending on whether the text is a main heading, or a sub-heading, or a sub-sub-heading. To change between heading levels, use these buttons: . I've had to help a couple of people who hadn't been found out about these buttons and were trying to change sub-heading formats manually. Not surprisingly, they made a complete mess of it.
It is good to use two heading levels to structure your text on the screen, but avoid using more than two levels.
Don't switch off all of the lights and stand in the dark so that people can see your slides better. You're giving a talk. It's about person-to-person communication. If people can see you, this will be much more effective.
Rehearse your talk and time it. Aim to finish one minute early. As a crude rule of thumb, you should not have more than one slide per minute of speaking time.
I see a lot of talks given by economists. There is a tendency for economists to include algebra in their slides. This is death to good communication. In my view, even if your audience is economists, only a minority can take in algebra off the screen quickly enough for them to really follow you. If you want to give a talk that only 10% of the audience follows, then fine, use algebra, but otherwise steer well clear of it. Use a flow diagram to convey the structure of your model.
If you must use algebra, you need to be sure that the symbols you use will be available on the computer you use to give the presentation. Some symbols you use may be installed on your computer, but not on the one you'll be using on the day, resulting in an equation full of odd symbols. To avoid this, you can tell PowerPoint to save the fonts used with the presentation. In PowerPoint 2003 you do this by selecting File | Save as | Tools | Save options | Embed TrueType fonts.
If you use foreign language characters or other special symbols, you can run into the same problem as for equations, and the same approach of embedding fonts will work for that too.
Face the audience and talk to them, not to your slides.
Don't put anything on the screen that you are not going to describe or read out. Never say, "I'll just let you read that" and then stand there silently. It doesn't work.
In any tables, all numbers should only be presented to two significant figures (e.g. 170, 34,000, 0.0052). Any more than that makes it harder to read and harder to compare numbers. If you think that two is not enough, you're mistaken. Using three significant figures implies that, on average, you are accurate to within 0.5% (and possibly as little as 0.1%). Such a small difference is probably not real, and is certainly not important.
If you are pointing to the screen, never do so with your hand some distance from the screen. The audience will get confused about what you are actually pointing at. You should either physically touch the screen, or use a stick or laser pointer. Similarly, don't use the shadow of your hand as the pointer, as again it can be confusing - some people will try to follow where your hand is pointing, rather than the shadow.
I think it's important for the audience to be clear about which bullet point you are currently talking about. There are three of ways to do this. You could physically point to the bullet point you are now discussing, you could use "Custom animation" to make the bullet points appear one by one, or you could have only one point on the slide.
I have mixed feelings about Custom Animation of text. Sometimes it is quite good, if you are unfolding a story that is a bit complex and you want to help people build up the story point by point. On the other hand, it is probably best not to do it for every slide, as it slows things down, and it really inhibits navigation through the PPT if you need to go back to an earlier slide. Personally, I do use it sometimes, but only sparingly.
If you do use Custom Animation of text, dim the text that you have finished with so that it doesn't distract people away from your current point.
Sometimes people have custom animation switched on but then just keep clicking until all of the text is displayed before they start talking. If you're going to do that, just turn off the custom animation!!
I prefer a template that uses light text on a dark background. In the last few years, the quality of data projectors has improved a lot, so that dark text on a light background is now at least possible, but light on dark is still easier to look at.
Many guides to giving a talk say that you should include a slide that outlines the structure of your talk. These days I rarely do this. I've reached the conclusion that it doesn't really help. It's better to spend your precious time getting into the story.
PowerPoint offers a huge range of options for transitions between slides. For example you can select Checkerboard Across, Comb Horizontal, Cover Left, Cut, Dissolve, and so on. They are all different ways of removing one slide and replacing it with the next one, mostly with lots of fancy movement. My advice is: don't use any of them. They are visually distracting and they don't help. In my opinion they don't look very professional. Just use the simplest and most basic default transition, where one slide just disappears and the next instantly appears. .
The same advice applies to the use of custom animations (for individual elements of the slide). If you use custom animations, just use "appear" and "disappear", not the fancier options.
Learn the basic key strokes that you can use to move around in a presentation. (Thanks to Tom Croft for highlighting this point.) I've seen an amazing number of people stand up to give a presentation and have to ask which keys to press, especially if they need to go backwards. Some don't even know how to get from one slide to the next! Here are the basics:
Next slide: N, spacebar, enter, page down, down arrow, right arrow, or left-click mouse. Personally I always use the spacebar as it's big and easy to hit.
Previous slide: P, backspace, page up, up arrow, left arrow. Backspace is the largest and easiest to find of these keys on most computers.
Go to a specific slide: with the slide show still running, type in the slide number (it doesn't display anywhere) and press enter. Alternatively, press ctrl-S and you get a menu of the slides. These commands are particularly useful if you have custom animations that you want to skip over.
Go to first slide: home
Go to last slide: end
Break out of the slideshow: escape (you don't have to go to the end of the slideshow). Escape is much better than right clicking and selecting "End show".
Here's a tip from
Stephen Loss: "A useful PowerPoint tip I picked up during a training session a
few years ago was pressing the "B" key to blacken the screen during a
presentation, and simply pressing "B" again to bring it back. I find this useful
if you want the audience to focus on you for a short period. You see people in
meetings using files or books to put in front of the projector. The "B" key is
so much easier!!"
Try to include something unusual or memorable in your talk. A physical prop can be a good thing. For example, a professor at my university takes along a baseball bat and hits balls into the audience to illustrate one of his points.
Every talk you give is a chance to impress people that you know what you're doing and can communicate it clearly. It's worth taking the time and effort to prepare well.
David Pannell, The University of Western Australia, David.Pannell@uwa.edu.au
The Trouble with PowerPoint, BBC Magazine.
Pannell Discussions are brief pieces on issues and ideas in economics, science, the environment, natural resource management, politics, and agriculture.
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