"X Marks the Spot"
The Magician removes a deck of cards and a Sharpie Marker from his pocket. He signs his name on the face of a random card and shows his signature to the audience. The deck is then shuffled and given a cut, losing the signed card somewhere into the deck. He then hands the deck to the spectator and asks her to shuffle the cards behind her back, so that the signed card is lost even further into the pack.
He hands her the Sharpie and asks her to draw an “X” on the back of a random card while holding the deck behind her back. Then, she gives the deck another shuffle, losing it once again into the pack. She hands him back the Sharpie and places the deck face-down onto the table. The cards are spread out revealing one card containing an “X” on it’s back. The card is revealed to be the same card that was signed by the Magician. The cards can all be examined and none of the others contain any marks.
Items required; 1 deck of cards, 1 standard Sharpie Marker and 1 dried up Sharpie Marker that does not write. Sign your name on the face of a random card using the Normal Marker. Then hold the same card behind your back and draw an “X” on it’s back. (NOTE* This will make the “X” mark more realistic). Blow on the ink to dry, then place the signed card on the bottom of the deck. Place the cards in the case and place the case and dried up Sharpie Marker in your pocket.
Remove the deck from your pocket and remove the cards from their case. (NOTE* Be careful not to allow the spectators to see the bottom card of the deck, because it will be the card containing your signature). Remove the dried up Sharpie Marker from your pocket and pretend to sign your name on the face of the bottom card of the deck. Show the signature to the spectators and explain this will be your card. Shuffle the cards losing the signed card into the deck. (NOTE* Be careful not to allow the audience to see the back of the signed card). Hand the deck to the spectator and ask them to hold it behind their back and give it another shuffle so that not even they know where the signed card is.
Hand them the dried up Sharpie Marker and ask them to draw an “X” on the back of a random card while holding the deck behind their back. Once they are finished, take back the marker and place it into your pocket. Ask the spectator to give the cards one last shuffle behind their back. Once they are done shuffling, spread the cards out face-down onto the table and remove the card containing the “X” on its back. Turn it over revealing it to be the signed card. The rest of the deck can be examined so that the spectators do not think that every card in the deck had a signature on it.