In making a pitch for funding, communicating with co-workers, making a sales presentation, or just giving a speech, a good PowerPoint deck or a set of keynote slides have become a must. Over the years, styles have changed with the advent of new technology features, but there are some basic rules that have endured.

"Less is more" is the most important rule—and the most frequently violated. For example, I just sat through a presentation in which there was so much information contained on each slide that I quickly lost what the group was doing. Slide after slide of more and more and more. The slides were unreadable and the concept was muddled. So I finally did something that I never do which is stop the presentation and simply ask: What are the three things you want me to understand? The presenter couldn't answer me directly, so then I tried the old elevator pitch gimmick—What would you tell a potential customer on an elevator? The CEO started to answer my question and, after about 30 floors of explanation, I asked the members of the team to leave and to e-mail me once they get their business figured out.

Here's a tip: Complexity does not sell. There may be thousands of cool features to your new product or technology, but listing them just puts people to sleep. Find out what the key elements of your pitch are, and then boil down the presentation accordingly. Add graphics, pictures, tables—anything to break up big concepts and communicate them simply.

I think it was Mark Twain that said, "If I would have had more time, I would have written you a shorter letter."

Keep it simple.