The CEO of a large company lost the audience—his top salespeople—in the first two minutes of his presentation. I was there to witness it. Slides were out of place and financial data was wrong.

Sorry guys. I threw this together last night,” the CEO explained as he stumbled along for an agonizing hour.

If you want to stand out there’s a simple way to do it: rehearse again, and again, and again. Let me put this in perspective. The organizing committee had spent months preparing for the annual sales convention. They scouted venues, purchased meeting space and rooms, made travel arrangements, and booked speakers. But the CEO couldn’t make time to craft, practice, and deliver a memorable kick-off that would fire up the sales team. This happens far too often. If you want to stand out there’s a simple way to do it: rehearse again, and again, and again.

When I was conducting the research for a book on the presentation secrets of Steve Jobs, I spoke to a reporter who had covered the Apple cofounder and who recalled an experience in which she was kept waiting for three hours as Jobs stood on stage in front of a largely empty auditorium, practicing every line of every slide and meticulously rehearsing every demo. Steve Jobs made presentations look effortless because he put a lot of effort into rehearsing them.

AP Photo/Christophe Ena, File

A Steve Jobs presentation was like a Broadway show. It had props, a set, a cast, a script, and beautifully designed backdrops (slides). A great presentation is a show complete with drama, conflict, humor, and entertainment. You wouldn’t expect to put on a first-rate performance without rehearsing, would you? A mission-critical presentation is no different and should be approached with as much effort.

In the bestselling book, Grit, University of Pennsylvania psychology professor Angela Duckworth argues that talent alone is not enough; high achievers combine passion and perseverance. “Our potential is one thing. What we do with it is quite another,” she writes. Perseverance requires practice…a lot of it. High achievers refuse to be outworked, period. They want to grow and they put in a lot of work toward that goal. According to Duckworth, if you track the development of high achievers, you’ll find that their skills improve over time and those skills improve because they engage in what professor Anders Ericsson calls “deliberate practice”—they practice a skill, solicit feedback, and do it over and over and over.

Deliberate practice applies to the skill of public speaking. If you track the biographies of great speakers like Winston Churchill, Martin Luther King, Jr., or Ronald Reagan, you’ll find that their signature speeches were delivered after years of deliberate practice.

How many times should I practice my presentation?

It’s a common question that doesn’t lend itself to an easy answer. I spoke to a famous TED speaker who practiced her 18-minute TED Talk two hundred times over a period of three months before taking the stage at the annual conference. It worked out for her, but most business professionals don’t have the luxury of that kind of time.

Anders Ericsson came up with the “10,000-hour rule” for high achievement. It takes 10,000 hours of practice over 10 years to achieve world class excellence. While the 10,000-hour rule applies to the improvement of public speaking skills over time, it doesn’t help you much for your next presentation. I have another rule that I call “The magic power of 10.” If you can practice your presentation out loud, clicker in hand, at least ten times, you will be significantly more confident, comfortable, and polished.

I know a famous pastor who speaks to 40,000 people every Sunday and millions more on television. He told me that, beginning on Friday, he practices his 20-minute sermon anywhere from 10 to 12 times before his live, televised performance. It’s enough practice time to commit your opening and concluding thought to memory and to rehearse the main message for each slide or concept.

The key is to rehearse the presentation as closely as possible to the actual delivery. If you stumble, make a note of it and keep going. If you want to replace an image on a slide, make a note of it and keep going. Rehearse from start to finish. Ideally, your last practice should be a full dress rehearsal in the actual auditorium or conference room where you’ll deliver the presentation. Get to the room early to make any last minute adjustments.

Finally, once you’ve practiced at least ten times, rest assured that you’ve mastered the material. The last thought that should cross your mind is smile and have fun. Now go put on a show.