Case The Joint Once Cohen has the basics of his act down pat, he makes sure to check out any new place he'll be performing at early in order to do what performers call "treading the boards"—figuring out where in the room it's best to stand (or sit), what planned elements of the show will have to change due to the specifics of the room, and whether there are any objects or features of the room he can incorporate into his act. Cohen says that he's gone as far as breaking into rooms before his act in order to do this sort of advance work.

"Usually I'm dealing with very high-end executives or party planners and really don't have a second chance to make a good impression," says Cohen. "I need to make sure all the minutiae are going in the right direction before I even start to show them anything."

Pincus agrees that getting familiar with a presentation venue in advance makes good sense. Not only does it reduce nerves, it also allows a presenter to adapt to any last-minute changes that might be necessary, such as dealing with equipment constraints or adapting to a room that's much larger or smaller than envisioned.

Doug Staneart, the C.E.O. of presentation training firm the Leader's Institute, adds that without these types of on-site adjustments, presentations can end up looking canned and unoriginal.

Always Have Backup Plans "It's essential to have backup plans—not just one, but several," says Cohen. "The key is to know all the things that could possibly go wrong."

Cohen prepares graceful solutions for all kinds of situations: If he accidentally 'flashes' something to the crowd (like a coin in his hand or a handkerchief up his sleeve), for instance, or a volunteer from the audience forgets which card he or she was asked to remember (true to the tenets of his profession, Cohen won't say exactly what he does in those situations, but stresses that he has plans for any and every contingency).

Staneart agrees with Cohen's advice of thinking through the unexpected—particularly in situations where you might end up fielding questions.

"You need to know way more about your topic than you're actually going to present, so if the unexpected does come up, you're prepared," says Staneart.

Pincus also highlights the importance of being aware of certain common issues, like technology failures or having less time for a presentation than expected, both of which can foil an otherwise well-planned presentation.

"When people are in a stressful situation, any little mishap can throw them off," says Pincus. "But if they've simply thought through having some key messages ready, no matter what happens they'll be able to adapt to a situation."

Adds Cohen: "Leave nothing to chance; the key to a successful performance is approaching it like a total pro."