It’s Not About You, It’s About Them
Being a community manager gives you an "authority".
But don’t let the “authority” part throw you off.
Your community is about your members and building something great within your realm of expertise. If you go into it with the mindset of creating a community for yourself it will push people away. So, make sure you don’t let it be about you.
Would you want to join a group that just promotes itself all day? I know I wouldn’t.