- Determine the focus and point of the community. Write the description according to that so users know what to post.
- Set up rules that go along with the focus. If your community is about Pikachu and someone posts cat pictures, that's something that should probably be removed.
- Post some content but not too much. Don't want to make this your personal blog. You want others to participate.
- Advertise it appropriately. Post to new communities. When there is another post and comments discussing your topic, mention that you have a community dedicated to it.
Getting a new community up and running is actually pretty difficult. Many of mine on reddit failed. But a few of them took off.
They're pretty basic right now. Remove comments/posts. Ban users from the community. And edit the appearance / sidebar of the community.