(a) Except as otherwise provided, each required signal given by hand and arm shall be given from the left side of the vehicle in the manner specified in this section.
(b) A left turn signal is given by the hand and arm extended horizontally.
(c) A right turn signal is given by the hand and arm extended upward; except that a bicyclist may extend the right hand and arm horizontally to the right.
(d) A stop or decrease in speed signal is given by the hand and arm extended downward.
Structure Maryland Statutes
Title 21 - Vehicle Laws -- Rules of the Road
Subtitle 6 - Turning and Starting; Signals on Stopping, Turning, and Starting
Section 21-601 - Required Position and Method of Turning at Intersections or Crossovers
Section 21-602 - U-Turn on Curve or Crest of Grade Prohibited
Section 21-603 - Starting Vehicle
Section 21-604 - Turning, Slowing, and Stopping Movements; Required Signals