For anyone who’s not familiar with the Stack Exchange model, you gain reputation by asking (good) questions, and answering them such that other people vote for your answers. For freelance developers and consultants having a high reputation can even help to bring work in. While the site’s in an early stage (“bootstrap mode”) it’s easier to gain points too, so there’s some benefit in getting in there now (hint, hint).
It’s intended to be dev-centred, but there's no reason why it can’t cover most of the practicalities of “how do I set up a Facebook Page” etc, so feel free to create questions you know the answer to and even answer them yourself. The great thing about the system is that since it’s community moderated, and questions are tagged rather than put into categories, then the definition of “what can I ask?” is fairly broad.