Practice, practice, practice.
It's starting to be very important for me that the audience watches the show and goes, "Yea, I can't do that." Or, "I can't see that anywhere else." That's what makes people interested and keeps them coming back. Important for skill to be a necessary part of it and come across to the audience. Teller, of Penn and Teller, doesn't want you to believe in psychics because there is way to much planning and skill that went into the trick for it to be written off as "magic powers".