XP

Now take two of any objects, for example a brush, and touch both the rubber and real hand at the same locations. Try to keep the touches synchronized. Your friend should be able to see the rubber hand at all times. Keep this up until your friend seems really confused and or amazed. At this point, the rubber hand will feel like a real hand.

For special effects, get a third friend to suddenly stab the fake hand. Your friend will freak out and pull back his real arm.