If you want to be better at chins you must offcourse do them( captain obvious I know ), but from there
its many routes to take.
Here are two ways of doing it:
Do a total of 30reps each session and try over time to get more reps and fewer sets, when you are able
to hit 3sett x 10reps x bw, you can start to add weight or you can do more total reps, lets say 40reps or 50reps.
You can also start with something like 3x5reps and add a rep pr set each cycle, I started at 3x5 when I started
5,3,1 in the beginning of the semester and last session I did 3setts x 8rep + 2sett x 3reps( a total of 30reps )
This is perhaps a modest method, but it adds up over time. Think of it as similar to starting light, but instead of starting at a lower weight you start at a lower volum instead because you cant offcourse take of some pounds of your bodyweight like it where a barbell, that takes some serious training and dieting to do. ( Again I am captain obvoius lol ).
Hope that was any help.