Use all of them, and possibly add Reddit to that list!
For Facebook I'd create your own page (I can't tell easily if that's your personal page or not). It needs to be one like we have where people can like it.
I would consider all these sites as important. As an example, 35% of ALL our referred traffic comes either from HackerNews, Facebook, Twitter and Reddit.
It sounds a bit to me like your not really sure what you are trying to promote yet, you as yourself or a brand? It'll be a lot easier to go forwards when you know :)