Presentation software makes public speaking easy. Just outline your talk in bullet points, add some amusing clip art, a nice background, and maybe some stock music, and you are all set. Anyone can look like a pro. But if you have ever been on the receiving end of one of these talks—and who hasn’t?—you know that they can range from confusing to deadly dull. And yet, people continue to make presentations the same way.
Combining speaking with on-screen text can be difficult. Some speakers put text on the slides and then paraphrase it or go off on tangents during the presentation. The result is that they lose the attention of people who try to read what is on the screen. Other speakers read the text on the slides verbatim. This approach can be effective for emphasizing key points. But most people can read the text faster than the speaker can say it, which leads to boredom if the entire talk is presented that way.
When images are added to the slides, text can cause even more problems. This has been demonstrated for e-learning programs, but it also applies to presentations. In e-Learning and the Science of Instruction: Proven Guidelines for Consumers and Designers of Multimedia Learning, Ruth Colvin Clark and Richard E. Mayer cite research showing that people remember less when shown text and images together on the same slide than when they see the image alone with narration. Redundant text (text that is exactly the same as the accompanying speech) can improve memory, but only when presented by itself with no images. Images that are unrelated to the text also interfere with learning by distracting attention from the important points. Animation and music impair learning as well.
Other research has shown that adding extraneous information, whether to make the presentation more interesting, go into greater detail, or add technical depth, made the key points less memorable and reduced people’s abilities to apply what they had learned. (These findings apply to learning new information, and may not extend to cases where people are already familiar with the subject.)
If you want to create a memorable presentation, follow these guidelines:
Consider using no text on the screen, or at most short subject headings and labels in graphics. There is nothing wrong with a blank screen while you talk. People will be more focused on you, and you will come across as a more skillful speaker.
If you do use text, make it the same as what you say, and limit it to a few key messages. Do not paraphrase, explain, or elaborate on the slide text.
When speaking, stay focused on the points you want to make.
Show an image by itself on a slide, and explain verbally what it means. Avoid using text on the same slide as an image.
Use only graphics that add information to the presentation. Avoid clip art, stock photos, and other unrelated images.
Do not use music, animation, or other media that distract from the content of the presentation.