Teller: Spend more time on it than is reasonable
"You will be fooled by a trick if it involves more time, money and practice than you (or any other sane onlooker) would be willing to invest."
Magician Teller:
Sometimes, magic is just someone spending more time on something than anyone else might reasonably expect.
Source: Teller's Most Infamous Quote About Magic by Rory Adams.
Most magicians usually realize this for the first time when they pull off a complicated sleight that took weeks to master. It’s easy to realize that the effort you put in leads to the trick being fooling. If the spectator knew you’d spent hours and hours and hours practicing one particular move or memorizing the deck, they might be able to figure out the trick. They don’t, though. Their minds don’t even go there.
You’re operating beyond the limits of the expectations of the audience.
Sometimes, magic is just someone spending more time on something than anyone else might reasonably expect.
Related: Teller Reveals His Secrets
2. Make the secret a lot more trouble than the trick seems worth. You will be fooled by a trick if it involves more time, money and practice than you (or any other sane onlooker) would be willing to invest. My partner, Penn, and I once produced 500 live cockroaches from a top hat on the desk of talk-show host David Letterman. To prepare this took weeks. We hired an entomologist who provided slow-moving, camera-friendly cockroaches (the kind from under your stove don’t hang around for close-ups) and taught us to pick the bugs up without screaming like preadolescent girls. Then we built a secret compartment out of foam-core (one of the few materials cockroaches can’t cling to) and worked out a devious routine for sneaking the compartment into the hat. More trouble than the trick was worth? To you, probably. But not to magicians.