Most of the greatest magicians and card manipulators who have ever lived have made very good use of the simple pass or classic pass as it’s also known. It is an invaluable and indispensable sleight of hand and although it requires considerable practice to perform it smoothly, it well worth the effort.
When a spectator has chosen a card, cut the pack and ask the spectator to replace it on the lower portion before you replace the cut section of cards on top of it. As you replace the cards, slip the tip of your left little finger on the card and in between the two packets of cards. It’s important that you hold the outer ends of the pack tightly closed and, to reinforce an air of nonchalance, you riffle the ends of the cards a couple of times. Next, you take the upper portion of cards between the right thumb at the back and the fingers at the outer ends and lift it off. At the same time drop the left thumb under the lower packet and turn it face upwards. Without hesitating, shuffle the cards of the right-hand packet onto the faces of the lower packet. Do this in a relaxed fashion without looking down at your hands – this will help conceal the move.
As the spectator if he is confident that he will remember his card and then go straight into a shuffle. Turn over the pack and continue the shuffle. You now have the on top of the pack to do whatever you want to do with it.
NOTE: If you enjoy this type of card sleight you might want to learn about other pass techniques. There is quite a variety! eg. the invisible turn-over pass, the flesh grip pass, the jog pass, the finger palm pass and the Hermann pass. Read more on Wikipedia.