5 Ways to Ruin Your Next Presentation

3. Fail to Rehearse "I can't tell you how many times I work with executives who spend thousands of dollars on the actual presentation-in creating the presentation and on meetings to create it-and then they don't even rehearse it," Gallo says. "When you prepare and rehearse the presentation-out loud, over many hours and many days-you'll come across as much more engaging as a speaker and effortless."

Gallo says he's learned (from his research and talking to people at Cisco) that CEO John Chambers, who is known for being a terrific public speaker, rehearses quite a bit. "He will go over the slides and content of slides during many, many days prior to conference," he says. "He has internalized the content, and he's very fluid and smooth. And that's because he rehearses."

Gallo's Tip: Practice 10 hours for every one hour of the presentation (and that doesn't include creating the text and slide notes). Practicing in front of another person or a video camera will help even more, he says. "Most of the great presenters actually rehearse much more extensively than anyone else," he says. "They don't just wing it."

4. Read from Your Slides "Most presenters who are just considered average or mediocre are usually caught reading the text on their slides," Gallo says. This dreadful presentation technique ties into Gallo Rule #2. "When you place a lot of text on slides," he says, "naturally you want to read from them, so you turn your back to audience and you read from slides on the display."

Unfortunately, people read from their PowerPoint slides much more than they think they do, Gallo notes. "When you read from your notes or from slides," he says, "that completely breaks the connection you have with audience."

Gallo's Tip: Practice your speech and know it cold, so that you can sustain eye contact with your audience while you are presenting. "Great presenters will do this: They glance at a slide just for a second to prompt them for the next piece of information," Gallo says. "And then they turn and deliver to audience. They know what's on the slide because they have practiced."

5. Ignore Your Body Language and Vocal Delivery "We know through research that 93 percent of the impression you leave on somebody has little to do with content and everything to do with body language and verbal ability-how you talk, sound, look and what you're wearing," Gallo says. "Only about 7 percent of the actual words or content is important."

However, he says most presenters will spend 99 percent of their time preparing the content and slides, and very little-if any-on understanding and controlling their body language and how they speak and sound.

Gallo's Tip: Grab your digital video recorder, deliver your presentation and watch yourself, he says. Watch for these key factors: eye contact (you should be making eye contact 90 percent of the time); posture (don't slouch, stand up straight and natural, and avoid putting your hands in your pocket); voice (don't speak in a monotone voice).

"You don't need an expert coach to be there to find these things," Gallo says. "You'll pick out one hundred things on your own that are annoying or maybe are some bad habits that you never knew you did."

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