The sign for "when" is
made by holding your left index finger up. Your palm should face right.
Bring the tip of your right index finger near to the tip of your left index
finger.
Circle the tip of your right index finger in a clockwise motion around
your left index finger and end with the tip of the right index finger touching the tip of the left finger. The movement is in the wrist. Your arm
doesn't move much on this sign.