V C Section 22111 Hand Signals
22111. All required signals given by hand and arm shall be given from the left side of a vehicle in the following manner:
(a) Left turn-hand and arm extended horizontally beyond the side of the vehicle.
(b) Right turn-hand and arm extended upward beyond the side of the vehicle, except that a bicyclist may extend the right hand and arm horizontally to the right side of the bicycle.
(c) Stop or sudden decrease of speed signal-hand and arm extended downward beyond the side of the vehicle.