i've found that doing push up's consistently and lifting benching/butterfly press/ etc all increase your pushup's.
I do this pushup routine its kind of like a ladder. 10-1, and then 1-10.
You never break form, you can take as long of a break you want after every number but are not allowed to break form.
starts like this: 10,9,8,7,6,5,4,3,2,1,1,2,3,4,5,6,7,8,9,10.
i almost finished 8 on the way back up but couldn't hold it anymore.
with 1 arm pushups they are really hard if u don't spread out ur legs for balance. without the balance i could do 1-2 with my left army only.
i've been trying for years to do a 1 arm pullup/chin up. 30 was my max and i still couldn't get myself to budge. Hey i figured if jet li could do it, it should be humanly possible but somehow it still seems a long ways away.