i started doing 10 push ups, resting three minutes, then doing ten more. at that time i could only do about 3 sets of ten before i just got tuckered out, but i would continue to do as many as i could, 3, 4 or 5 push ups until i reached total failure. after a week or two i could do about 5 sets of ten with 3 minutes of rest between each set.
well, a few months later i could do 20 push ups per set, rest 6 minutes, then do 20 more. i could do that for 10 sets, which gives you the ability to do 200 push ups in an hour. later i added more, until i was doing it twice a day, in the morning and in the evening, doing 30 reps per set for 10 sets.