If you come late to class, do 20 push-ups right at the door. Don't first
drop-off your bag, don't hide at the back of the room, do your push-ups
right at the door before you go take another step into the dojo.

If you can, do 20 knuckle push-ups; otherwise, do 20 regular push-ups.
If you can't do 20 push-ups - well, try not to be late :-).

Train hard.
--
Steven.