Some suggestions for sneaking a peek. You can hold the deck up in one hand with the faces toward you and tell your spectator to concentrate on the decks before you undertake the next steps. Or you can say that by focusing on the decks for a moment, you are creating a communal spirit that will lend itself to a surprising outcome. Use your imagination.
Once you have the bottom card firmly in your mind, youre ready to go. I find it helps if you repeat it three times in your mind.

