[header] How to condition your hands for martial arts training [title] Begin slowly. [step] Get used to forming and shaping your knuckles by doing fist push ups while standing and using a wall. Do the push up as you would on the ground. 
By doing them on the wall, it helps not to put too much pressure on the knuckles of the first two joints. This also helps getting the muscles used in doing push ups to get stronger and also hits the muscles at a different angle.