This is a nice little physic card trick that really depends on your showmanship to help sell this effect. Whenever you do a physic trick you should really sell the idea that you have physic abilities
The magician pulls out 5 cards from the deck. The cards are the ace,2,3,4 and 5 of any suits they could be all the same or all different it doesn't matter. Lay them down on a table in order. The magician asks the spectator to mentally think of 1 of the cards and not to tell them. The magician then asks the spectator to hold out his dominant hand. The magician tells the spectator that the thumb represents the ace, index finger 2, middle finger 3 and so on. The magician tells the spectator to concentrate on the finger that their card represents. The magician lightly taps the tip of the spectators fingers with the tip of their index finger. The magician can then correctly predict the selected card.
The secret is really simple when you ask the spectator to concentrate on the finger that represents their card they will unconsciously stiffen that finger. So when you tap them gently you will be able to tell the card they picked. But when your doing this only tap gently and don't wiggle them just tap them with the tip of your index finger and you should be able to tell. If some are a bit stiff start to eliminate the cards that have the looser fingers and keep asking them to really concentrate on that finger.