Effect:

Keep a card in your own pocket, and another one in the volunteer's hand. With your magical power, make the two cards switch places.

Procedure:

1. Remove 2 cards from the top but make it seem as if only one card is taken out (double lift). Show the bottom card to the audience and put it back on top of the deck.
2. Then, take the card that is really on top the whole time, and put it in your pocket.
3. Now, do another double lift, show the card to the audience, put it back on the top of the deck again, and take off the top card which is actually the card everyone assumes to be in your pocket.
4. Leave that card faced down on the volunteer’s hand, and ask him/her to cover the card so that there is no way you can physically touch the card in their hand.
5. Now, say something like: "I'm now going to switch the card in your hand with the card in my pocket using my magical power." While distracting everyone with that announcement, secretly palm your hand on top of the deck and remove the top card which is supposedly in the spectator's hand and put it in your pocket while you are taking out the card you hid in your pocket earlier.
6. Now, you take out the card you are hiding in your palm, and ask the spectator to turn the card in their hand over, and it will look like you really did switch the two cards with your magical power.