The first is to create a hashtag for your community.
Deliberately create and spread a hashtag members in your community use. It helps Twitter newcomers find your community and encourages conversations elsewhere. But better, every member who uses it promotes your community to all their followers. Be sure to stream the conversations through your community page. Fresh content galore.
The second is to create a community from a hashtag.
Hashtags are simple, immediate, communities. It’s a group of people who have decided to be part of something. You can use a hashtag to try dozens of community ideas. See what takes off. Or you can be more tactical. Find ten key influencers to begin using a certain hashtag for a topic. No more registration pages, just add a hashtag to join a community.