What are the proper hand signals to use when riding a bike?

When riding a bike, it is important to use hand signals to communicate with other road users. The proper hand signals to use are:

1. Left turn: Extend your left arm straight out to the side.
2. Right turn: Extend your right arm straight out to the side, or bend your left arm up at a right angle.
3. Stop or slow down: Extend your left arm down at a right angle.

Remember to always check for traffic before making any maneuvers and use these signals to indicate your intentions clearly to others on the road.