Too many people think the secret to a great presentation is a dazzling PowerPoint presentation. Not quite. Whether you’re an occasional presenter or a seasoned pro, the answer is the same as the punch line to that tired joke: “How do you get to Carnegie Hall?”

It’s practice, practice, and more practice, pure and simple. The people who deliver presentations that seem to be so natural and casual are usually those who have practiced the most.

I learned that lesson a few years ago in a conversation with Tom Mucciolo, who is widely recognized as a presentation guru. If you are a frequent presenter, his books (just Google his name to find them) will help you make both your slides and delivery more effective. When I asked Tom how he was able to come across as so relaxed and natural during presentations, he said it was the same thing that made actors and actresses seem so convincing. They keep rehearsing what they present until it becomes completely comfortable.

Tom said that his minimum standard for practice was 12 times the length of the presentation. In other words, if you’re going to make a 15-minute presentation, you should rehearse it for no less than 3 hours. That may sound obsessive, but I’ve applied his standard to my own presentations, and I’ve found that I’m much more comfortable and appear to be much more relaxed when I can repeat the material in my sleep.

Presenting is like any skill — the more you do it, and the harder you practice, the better you’ll get. Simple, but it works.