Wow, I hadn't thought of this little trick in many years. If memory serves (from 1988) this is how it is done. In this example, you'll be demonstrating the trick on a friend. You'll be using both hands, one to lock off the wrist, the other to rub some of the remaining blood out of
the hand. For this to work properly, your friend will need to make the tightest fist possible.
1. Ask your friend to hold out their hand (palm up). Tell them that when you slap their hand, they should make the tightest fist possible.
2. Gently slap their palm and after they make their tight fist, wrap one of your hands around their wrist. The purpose of this is to slow the blood flow to the hand.
3. Use your other hand to squeeze and rub the remaining blood out of their fist. You should do this for a minute or two. The hand should turn
very white if done successfully.
4. Ask them to slowly open their hand, but keep your other hand locked on their wrist.
5. Touch each one of their fingertips, and act like you're pulling an imaginary objects out them. This is just to enhance the effect.
6. Release your grip on their wrist, and then gently pinch the center of their palm, and then slowly move upwards as if you were pulling a thread from their palm. To them, it should feel real.