Four days ago I started doing push-ups following theComics, Films, Kung Fu, and Whatever the Hell Else. I'm starting easy since I've never been a particularly athletic guy but I'll try to improve fast.
The routine consists of picking a number of push-ups to do (I'm doing Elroy's gentle 100). On day one you do 100 over the course of an hour. The next day, you do 100 hundred sometime throughout the whole day. Then you repeat. You do this for ten days and then rest for two days. After the two days of rest, you try to do as many as you can in one go. Then start all over again with a larger number of push-ups.
I don't know what Batman would think about two days of rest but I think in the real world there's wisdom in giving yourself a break of some sort.