(a) A person operating a bicycle shall give hand and arm signals as follows:
(1) Left turn. — Left hand and arm extended horizontally and to the left side of the bicycle.
(2) Right turn. — Right hand and arm extended horizontally and to the right side of the bicycle or the left hand and arm extended upward.
(3) Stop or decrease speed. — Left hand and arm extended downward from the left side of the bicycle.
(b) A signal of intention to turn right or left when required shall be given continuously during not less than the last 100 feet traveled by the bicycle before turning, and shall be given while the bicycle is stopped waiting to turn. A signal by hand and arm need not be given continuously if the hand is needed in the control or operation of the bicycle.