1. Place the mechanical arm on the desktop and hold both ends of the mechanical arm with both hands.

2. Bend both ends inward to make the arm arc.

3. Fold the left and right sides of the arm inward to make the arm round, and the ends of the two arms are close to each other.

4. Bend the middle part of the arm downward to make the arm show a "U" shape. At this point, the red and blue manipulator has been folded.