Promoting the community via social networking channels and elsewhere.

If your goal is to have a large, public online community, you’ll need to make promotion part of your strategic plan.

Send an invitation to your email list (your newsletter, key contacts, etc.)
Start participating and visiting other sites where your target audience gathers (be careful not to just jump in and promote your own thing...establish yourself by helping others first and let it happen organically)
If you have employees, make it a priority for your entire team to help draw people into the community

Leverage Social Networks

There are several things you can do to leverage your social networks to promote your community:

Include a link to your community in the profiles of all your social accounts.
Start a relevant hashtag or participate in an existing one that works for your community.
Add social embeds or feeds to your community, on a custom page or within posts.
Vibe off of the short status updates that happen in the social networks to start longer discussions in the forums...post a Tweet as a topic and then spark a bigger discussion.
Remove login friction by adding social login tools, so that your forum members can log in using their existing social network credentials.
Post updates from the hot topics in the forums out to social networks, with a link back to the community.
Promote special events, offers, or contests from the community in your social accounts.
Add space in your forum registration for members to add their other social networking handles, links, etc., so members can connect with each other and further strengthen relationships.
Promote within your Facebook groups and newsfeed and include links to your community on your LinkedIn corporate profile (or personal profile if appropriate).

Don’t forget IRL

Even though your community is virtual, your members (and potential members) live in the real world too. Don’t forget these options for promotion:

If you have a retail store, put up signs in your physical locations; consider QR codes too.
Promote your community on all corporate items (business cards, swag, stationery, if you have it).
If you are already running traditional ads (radio, TV, billboards, vehicle wraps), include your community there, as well.
Do you have access to celebrities or experts? Use them to draw interest. Members love the ability to get insider information or interact with people who are normally not accessible.
Start some in-person gatherings with your community (or let your community create their own meetups).

Promoting The Community

Growing Membership