Honestly, simply reading `man bash` from start to finish was one of the best things I ever did. I started doing it with all sorts of stuff. May I suggest you start with `man man`?
Then someone told me about `apropos` which is summarized in it's man page as "search the whatis database for strings". Sooo useful. Not nearly as useful as simply reading man pages from start to finish, but I've only got so much spare time.
Reading `man` is the kind of thing you understand after years of hitting hard walls. Even now I still despise it even though I know most of the answers are in it. I think I want something less linear to search into, oh and I'm surely a lazy P*S too.
Then someone told me about `apropos` which is summarized in it's man page as "search the whatis database for strings". Sooo useful. Not nearly as useful as simply reading man pages from start to finish, but I've only got so much spare time.