Back when I got involved in NancyFX, I started by just contributing to the documentation to make it easier to understand, filled in the missing pieces that I had to learn or annoy people by asking questions.

The only downside was after a couple of years, in the chatroom people would ask a question that 95% of the time resulted in just linking them to the docs and they said thanks it solved the issue. The other 5% was either not supported or resulted in improved docs.