My 2 cents: try to become a moderator of discussions for a while. People are talking? Instead of contributing, try to watch them. Are there People who contribute more/less? Does someone have problems to get their turn? Do they understand each other? Try to make space for those that need it. By the end of the discussion, if there was something really important to the topic that noone mentioned, say it. This approach helped me a lot to become more aware of the multiple people conversation dynamics and in the end helped me with dialogs as well.