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PowerPoint presentations: a speaker's guide
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By Geoff Hart
Previously published as: Hart, G.J. 2004. Powerpoint presentations: a speaker's guide. Intercom March:25–27.
Vinton Cerf, one of the founding fathers of the Internet, reportedly parodied the well-known quote about the cost of attaining power, observing that if power corrupts, "PowerPoint corrupts absolutely". Pointed though Cerf's statement is, it places far too much blame on the software. After all, speakers must take some responsibility for their presentations. As in any other form of communication, you must decide what you're going to say and how you plan to say it. But once that's done, you need to use all the skills at your disposal to make the chosen medium work for you.
Let's assume that you've chosen to make an oral, computer-based slide presentation, whether with PowerPoint or any of its competitors, and that you've practiced the material well enough to speak comfortably on it. Now your task is to create a presentation that will support your talk. Although a well-crafted, well-delivered speech can often succeed without visual accompaniment, presenting a message in two media (spoken words combined with onscreen text, for example) can improve retention of your message. Here are ten things to keep in mind as you develop your presentation.
People are present to hear you speak, not to read slides; if you feel they would be satisfied reading slides, stay home and send them a printout or a self-running presentation file. The true value of a presentation is what you have to say, plus your ability to expand upon your original message if the audience seems to be missing the point or raises questions. Use the slides to support your talk, not replace it. Visuals should help the audience understand and remember what you're saying, so design the onscreen information to support that goal.
Since reading slides is as deadly as reading a prepared speech, use the slides primarily to remind you of what you wanted to say and to focus the viewer's attention. It's natural for viewers to want to read the text you present, so take advantage of that desire and use the projected images to provide context for what you're about to say.
The more time people spend reading text, the less attention they can devote to you, so keep text as short and focused as possible. Onscreen text should summarize the point you're about to make, not provide all the details. A well-designed screen typically contains a title that provides the overall context, an introductory line or heading that specifies what you'll be talking about in that context, and no more than about four bullets of five words each. [Looking back from 2005: A kind reader pointed out to me that this statement could be taken as an absolute rule. It's not. Treat it as a desirable goal, and use more words when that's necessary.—GH] If you have more to say, consider using several slides rather than cramming the information into a single slide.
If you want the version of the presentation that you distribute to include the text of your speech rather than just the bullet-point summary, include that extra text using the "speaker's notes" that PowerPoint and its competitors provide. This information will be visible when you print out the presentation, but not when you display the individual slides. If you don't know how to use this feature, provide the information in the form of a printed handout. PDF files available for downloading are another option.
Whether to provide the handout before or after your talk is hotly debated. If the audience receives the handout in advance, they'll be less inclined to try to write down all of the information on your slides while you talk; on the other hand, they may spend more time reading your handout than listening to you. One suitable compromise involves providing the handout far enough in advance of the talk that your audience has time to skim through it before you begin speaking. That's particularly important if you'll be displaying large or complex graphics that will be difficult to see onscreen; handouts let you describe things in print that would be impossible to show on the screen. If you choose to provide the handouts after your talk, explain to the audience beforehand that it won't be necessary to record each screen.
If you present multiple points on each screen (most commonly in the form of bullets), bring these points onscreen one at a time, not simultaneously. Audiences will try to read everything on the screen, and while they're reading, they're not listening to you. So present the information in bite-sized chunks, pausing long enough between chunks for the audience to read the five or so words that I recommended—typically no more than a few seconds.
Never trust that what you expect to appear onscreen has actually appeared. In an ideal setup, you can see what's onscreen by pressing the "next slide" button on your laptop—you don't have to turn your back to the audience, and the audience has time to read each line of text. (Be aware, however, that it's easy to accidentally tap the "next slide" button twice. Learn how to retrace your path when this happens.) Less ideal setups may force you to stand sideways so you can keep one eye on the screen and the other on your audience.
For a presentation to be legible, the signal must stand out from the noise; that is, the text and graphics must be legible against their background. Black text on a light background (for example, ivory or pale yellow) provides maximum contrast without relying on a glaring white background that strains the viewer's eyes, particularly in a darkened room. But white or off-white on a dark blue background and yellow on a dark green background also work well, and may be easier on the viewer's eyes.
Try to limit yourself to two typefaces if you're not producing a presentation on typography, since unnecessary typographic changes draw attention to the type at the expense of the message. One typeface for titles and one for the main text should suffice for most purposes. Whether to use serif or sans serif type is less of an issue than it used to be, since serif typefaces designed for onscreen use can be every bit as legible as typical sans serif typefaces; in fact, the serif font is sometimes more legible, since many sans serif fonts make it difficult to distinguish between lowercase L, I, and the number one.
The type must always be large enough to be read at a distance. To test legibility, stand about 10 feet from your monitor and ask yourself whether you can read the text easily: if you can't read it, neither can your audience. Please note that 10 feet is only a crude estimate: In practice, you should stand far enough away that your computer monitor appears to be the same width as the projection screen will appear to viewers sitting at the back of the conference hall.
It seems obvious that you should use graphics to communicate graphical concepts ("a picture is worth a thousand words"), but you'd be surprised how often this isn't done—or is done poorly. (Of course, if you've sat through as many presentations as I have, maybe you're not surprised.) Unfortunately, most graphics appear in the form of weird lines or shapes superimposed on the slide background. Although these graphics improve the esthetics of your presentation—in those rare cases when the audience actually shares your taste in objets d'art—more often they simply clutter the screen, make it harder to read, and distract the audience.
Instead, use graphics that illustrate what you want to say, and use a pointer to direct attention to features of the graphic that you want to emphasize while you talk. Be wary of laser pointers, since they often dazzle the viewer's eyes; a yardstick or a telescoping metal stylus often work far better. Better still, emphasize the key parts of each graphic directly in your presentation software by adding graphical pointers (arrows that point to or circles that surround the point of interest) one at a time as you talk. If you don't know how to automate this process so that new pointers appear and old ones disappear each time you tap the keyboard, use a new screen for each image. Avoid overwhelming viewers with a myriad of highlighted information.
If you do present graphics, simplify them as much as possible. The principle of "abstraction" means that you should show only the visual features that most directly concern the viewer, not all possible features. For that reason, an illustration is often simpler and clearer than a photograph. In technical communication, software screenshots are a mainstay of our graphics both because they relate strongly to our typical topic and because, if you're like me, you can't draw a straight line with a ruler, let alone create a convincing illustration. But nobody can read an unenlarged Excel spreadsheet onscreen. Where possible, crop and enlarge the image to focus only on the details you're discussing.
As a general rule, eliminate all multimedia effects, particularly the fancy whizbang sounds and transitions that most presentation software now offers. It is possible to use animations and sound effectively, just as it's possible to run a mile faster than 4 minutes—but few of us can do either. The main exception, of course, is when you can't communicate a concept in any way other than using sound or animation. It's not possible to communicate music well without actually playing the music, and the motion of objects is best handled with moving video. Just remember that even though skillful use of multimedia can improve communication, unskilled use can distract the audience into paying so much attention to the media that they forget the point you're trying to make. (Usability expert Jared Spool reported exactly this effect in one example of "talking heads" videos used in online help: Viewers really liked the help file, but retained less information than in a traditional version with only text and static graphics.)
Learn to use your software's template features rather than building each screen from scratch. Consistency is important indeed in a presentation, since visual objects such as logos that jump from position to position between slides draw the eye; the viewer ends up playing "Where's Waldo?" instead of concentrating on your presentation. That's also true of colors, fonts (typeface and size), and layout. Don't change anything randomly—change it to make a point by drawing the eye intentionally to something you want viewers to focus on.
Novelist Terry Pratchett once remarked that "wisdom is one of the few things that look bigger the further away it is." That's particularly true of presentations. If you want your presentation to hold up to close scrutiny and still make you appear as wise as you undoubtedly are, keep it simple and straightforward by following the tips presented in this article.
©2004–2017 Geoffrey Hart. All rights reserved