(1) All signals herein required to be given by hand and arm shall be given from the left side of the vehicle in the following manner and such signals shall indicate as follows:
(a) Left turn.—Hand and arm extended horizontally.
(b) Right turn.—Hand and arm extended upward, except that a bicyclist may extend the right hand and arm horizontally to the right side of the bicycle.
(c) Stop or decrease speed.—Hand and arm extended downward.
(2) A violation of this section is a noncriminal traffic infraction, punishable as a moving violation as provided in chapter 318.