How do I create a community?

Maybe there's just some setting because I'm new here. I don't know but it seems really hard for me to find this. I checked in the settings. It's not on the main dashboard. I'm not sure how to participate other than to comment into the handful of communities that I'm already a part of and I can't even find the ones I hope already exist. I'm sure they already do but I just don't know where they are or how to find them. Halp!