the thumb he takes the coin to the back side of hand where he had applied the gum stick. the magician pretends that he is squeezing the coin, but in fact, there is no coin in the hand. and when opens the hand there is no coin.
the magician should be careful while showing hands to the audience that the coin should remain invisible to the public and that it may not fall.
the magician takes a coin in one hand and passes it to the other hand. and he closes his hand. after few seconds when he shows his hand there is no coin. wow, but how this happened?
as shown in 