Everyone’s an expert in their own experience. Look for opportunities to invite conversation around those. Also, stay involved in the conversation you host.
What does your audience want to talk about? How can you tap into their outrage, pride or excitement? There’s also a a lot of humorous back-and-forth in the comments under this post.
Look for opportunities to productively challenge trollish comments. It respects the participation of the more constructive commenters and reminds people that you support civil conversations.