Nerves in your wrists are going to be screaming with pain no matter what you do. The least painful way is don't do it. There is no way possible to break your wrist without feeling some pain. If it's going to happen, it will happen when it happens. Don't try to break it, or fracture it. My friend broke 3 bones falling in gym, and she was crying all day it hurt so bad. Do you want to be crying all day because you took a fancy to break your wrist? :L I'm not trying to be mean but.........point is, the least painful way is to not do it at all. :)
The least painful way to break your wrist would be to not do it at all. There is literally going to be pain whatever you do.
If your to scared to jump on it or something, I don't think you could bare the pain of it. So um yeah don't go breaking your arm for no reason, that's just stupid...
What you can do is you get something hard and keep hitting your bones until you think it is broken I did it and it did pain but not as much as I thought it would lol BTW I don't care what anyone says about me breaking my wrist so say what you like.
If you want brake you' re wrist or elbow ( like I do) not for attention but for the cast I suggest you do half potato and half bend if backwards. You bend your arm backwards and hit it with a frozen potato or just a potato.( frozen works best) . You may need a friend to hit it for you or you could do it yourself. TA DAAAAAAAAA