THE SHUFFLED TEN.
Let a person remember the numerical position of a chosen card replaced in the pack. On taking the pack into your hand, bring a certain number of cards, say ten, from the top to the bottom.
Mentally take that number from the whole number of cards, fifty-two with a full pack, and boldly tell the company that the selected card will be the forty-second, reckoning from the card itself. If his card was the tenth, you count it eleven, twelve, thirteen, and so on, and his card will come out as announced.