You can use traditional push-ups (high, medium and low) to turn your palm into a fist.

When practicing, you should put a cloth or other comfortable soft object under your fist (to prevent calluses)

Others: you can stand on your head with your fist, hit sandbags, hit wall targets, (or tear up a thick calendar every day)

Second, improve the strength of the fist.

This is about practicing arm muscles, which can be assisted by dumbbells.

You can also push-ups or punch with your arms loaded.

Others: the overall strength should also be practiced! The waist should be coordinated, and the combination of waist and horse can improve the power of punching.