Hold your hand out in front of you, with the palm face-up. Drop your hand back towards the floor, stretching the palm side of the wrist. Use your other hand to bend your hand back even more ...

Arguably, one of the most important of these hand signals involves bending your left arm down at a 90-degree angle with your palm facing backward ... the notion that the back of a motorcycle ...

You'll see them extending their left arm roughly 45° downward, with their palm open and facing forward. They'll then move their hand multiple times from back to front in an arc. At that point ...