To publish your community, go to 'Communities.' Select a community that is unpublished and click 'Edit'.
Once you are in the community, click 'Publish Community.'
As soon as you publish the community, it becomes active within the 'Communities' tab.
To unpublish a community, just click the 'Edit' button to access the community and click 'Unpublish Community.'
When you unpublish a community, none of your students or leads will have access to it.
Also, watch the video on 'Publishing and Unpublishing a Community'