What you need:

1.A deck of playing cards(52) NO jokers.
2.A willing volunteer.

Step 1:

THE TENTH CARD

Before your volunteer arrives make sure that you know the tenth card from the top,in this case the ten of hearts.

Step 2:

Now put the ten cards back in place, we will begin with the volunteer in the next step.

Step 3:

when your volunteer arrives,tell him/her to think of a number between 10 and 20.

eg. 14
I cannot take anymore pictures as my camera has stopped working.

Step 4:

ask the volunteer to deal out the amount of cards the he/she has thought of.

Step 5:

then, take the two digits of the number and add them together.

In this case 14 1+4=5.

Step 6:

take the answer and deal out the that number of cards from the top of the smaller pile.

Step 7:

Finally tell the volunteer to pick up the top card and tell them what it is,or draw it or something.

this is my first instructable so I hope I didn't do too bad.

enjoy and remember practice makes perfect.