What is the best way to improve accuracy for strikes (punches, kicks, elbows and knees)?

Question

Ive tryed hanging tennisballs on string but they fly off from the force

Answer 1

punching box with a target

Answer 2

practice on a friend helps a lot.

Answer 3

focus mitts. or a live opponent.

Answer 4

A double-end bag or a speed bag work very well, make sure that when you use these items you punch the same way that you would in a real fight, don't raise your arms high or swing out wide just to hit the ball, then you are not developing skill, but just trying to score "points." You can hits these ball with other "parts" as well, like elbows, but probably not kicks, (maybe with the double-end ball). Another good method if you already own a punching bag is to use a sharpy or marker to put a few small dots onto the bag at various spots (like where your nose is, etc.). Then practice hitting these spots with the middle of your fist at moderate speed, as you get better move faster, when you can throw 20 full speed punches at each dot move on to random shots between all of the dots. When you can throw 100 punches at full speed randomly picking a dot with each punch then move on to using foot work-  jump back and then forward while throwing a punch to a dot, jump to the side while punching a dot, start facing away from the bag and turn around quickly punching a dot as soon as it comes into view, etc. There are many variations you can use with this method. The nice things about all the above choices is that you can use full force punches, while with the tennis ball idea, which is actually a pretty good idea, you have to hit very lightly.

Happy Training!