Whether you're riding solo or in a group, you'll need to know the proper hand signals to alert others of your intentions.

1. Single file: Raising your left arm, bending the elbow, and pointing up with the index finger, it indicate that you want to form a single file in order to avoid congestion in the complex traffic section. It's necessary to cycling a single file, when the people over 2, when going outside, especially, in the city.

2. Double file: Raising your left arm, bending the elbow, and pointing up with TWO finger,  it's good for riding by two row in order to communicate and if the team over 5 people.

3. Turn Right: The first gesture is by extending the right arm straight out (90-degree angle) with your palm flat facing the ground. The second signal to turn right is by raising your left arm, bending the elbow, and pointing up with the index finger, historically, this practice is no longer in use to cyclists, and has been replaced with the simpler right arm straight out horizontally. The Uniform Vehicle Code in the U.S. recognizes both, although it recommends the right arm out approach. State traffic laws generally conform to the UVC, but exceptions may exist.

4. Turn Left:  When on the road a left turn is indicated by fully extending the left arm out, with your palm flat facing the ground. You can also signal with a bent elbow, but the straight arm out is more popular and more visible.

5. Avoiding obstacles: The index finger of the right hand is obliquely extended and points to a certain part of the right side of the ground, indicating that there are obstacles such as glass bottles or potholes at the place, reminding the rear teammates to pay attention to avoiding, and asking everyone to pass from the other side. If the obstacle is on the left side, extend your left hand. While doing the gesture, you can also call out “GLASS!”

6. Slow down: the palm of one hand extends obliquely to the ground, swinging up and down to take a ball, indicating that the road is more bumpy or has a car, prompting the rear teammates to slow down.

7. Follow me: With one hand palm behind you, swing back and forth toward the hips, prompting everyone to stay in shape and follow.

8. Avoid cars: Reaches out the hand to the side of the vehicle or pedestrian, and the palm is facing the vehicle to remind the car when passing the intersection.

9. After you: The right hand is on the side of the body, and the palms swing forward and backward quickly. It means change the leader, the team leader to speed up the two feet after completing the prompt, and then retreat on the left side of the team, the rider quickly fills in, the leader slowly retreat to the team.