Girl Scout handshake
A formal way of greeting other Girl Scouts and Girl Guides. You shake hands with the left hand and give the Girl Scout sign with your right hand.
 

Girl Scout sign
Made by raising three fingers of the right hand. This sign stands for the three parts of the Promise. You give the sign when:

Quiet sign
Raising the right hand over the head to signal for attention and quiet at any Girl Scout gathering. When the hand goes up, mouths go quiet, and everyone joins in giving the quiet sign.