I usually start by reading either the docs (if they are good quality) or a book (if the official docs aren't great) and then I code something trivial after that

I usually start by reading either the docs (if they are good quality) or a book (if the official docs aren't great) and then I code something trivial after that. If I'm using it for work I will likely be reading and trying to understand co-workers pull requests, and then progressively more complicated PRs of my own.