Rest the pencil on a table. Grab your wrist with one hand. Your other hand reaches from underneath to grasp your wrist.
Bring down your hand, palm down, to rest on top of the pencil. As you bring your hand down, secretly extend the first finger of your "grabbing" hand.
Rest your hand on the pencil and secretly shove your first finger underneath the pencil and hold the pencil against your hand, as shown in the picture. This is the exposed view that spectators would not see.
