It is required by law for drivers to use turn signals at least 100 feet before turning, reports the New York State Department of Motor Vehicles. Most vehicles have built-in turn signals that are used to signal your intention by blinking. However, if your vehicle's turn signals fail, you must manually signal your intention using your arm. Manual turn signals are the same for both vehicle drivers and bicyclists.
Roll down your driver-side window. This will allow you to make your turn signals visible to others.
Extend your arm straight out your window to signal a left turn.
Hold your arm out the window and bend it upward at a 90-degree angle to signal a right turn.
Hold your manual signal in place until you are about to turn, then return your signaling arm to the driving wheel.
