No person shall turn a vehicle at an intersection
unless the vehicle is in proper position upon the roadway as required
in § 1160 of the Vehicle and Traffic Law, or turn a vehicle
to enter a private road or driveway, or otherwise turn a vehicle from
a direct course or move right or left upon a roadway unless and until
such movement can be made with reasonable safety. No person shall
so turn any vehicle without giving an appropriate signal in the manner
hereinafter provided.