The practice of butterfly stroke needs to be divided into several steps, which is a gradual process. The first is the waist line and the backward action standard. The specific operation steps of correctly practicing butterfly stroke are as follows:

1, bend back naturally, not too much, and beat down the water to increase the propulsion.

2. Demonstration of butterfly retrogression error.

3. As the movement slowly approaches the water surface, look up and take a deep breath.

4. Then add the action of paddling with one hand.

5. Practice with one hand and start paddling with both hands, thus completing the whole butterfly stroke.