Hold the rubber band between your thumb and forefinger and close it at the first finger at the beginning of your fingertip. Remember to keep your middle finger with your index finger. Then put on the epithelial tendon.

Put the balloon mouth on the faucet and pinch it tightly. The pad below the balloon is about 5 cm away from the bottom of the balloon. The tap turned on a lot of water. When the balloon is filled with water, turn off the tap until it can bear it. Hold the lower part of the balloon. Water injection can be completed.