The Tag gimmick is two cards joined. One the face of the bottom card is a small punched out section. Have any card selected and signed, cut deck, place signed card on top of sticky card. Shuffle, remove cut out card, showing this is not their card, hide the cut out, punch a hole thru the top card (you are really punching a hole in the selected card. Thread Tag thru punch out, insert card into deck, have spectator pull Tag, their signed card is now fastened to the Tag!