Hey there, I run two online communities. The first is a Facebook group: https://www.facebook.com/groups/realtalkwithrachel. The second is an virtual support group http://rachelgrantcoaching.com/asca/.
Developing, facilitating these groups has been a process of trial and error and I'm happy to share my experience and best practices.
I recently wrote an article on how to be a trauma informed coach and many of those principles apply (attached here).