fingers facing me, i did 5. i probably could have gone for 6 and pushed for 7.
how many are you supposed to be able to do?
When I did chin-ups in army tests, 10 was considered "good" and 14 "excellent". I can usually do about 10, but never hit 15. There's no "supposed" number common to everybody. Some are natural chinup monsters and can do 20 without much trouble. Obviously being small and light is an advantage.
what excercises help w/chin ups? (besides do more chin ups)
Experts seem to agree that you just have to do more chin ups, high volume, constant good form (no kicking, squirming, etc., feet locked together, chin must always go over the bar). So if your max is 5, don't do 5 because that will tire you. Instead do many sets of 3. Or ladders: 4-3-2-1, etc. You want plenty of recovery time between sets, and don't start a rep you can't finish. Whatever helps you put out many clean reps total.
When I do chin-ups (as a supplemental movement, after benching), I usually aim for 25 total reps in the session. I pick a recovery time and rep count I think will get me there, while keeping the rep count as high as possible. For instance, I could do five sets of 5 with 2 minute rest.