I'm not sure where I first heard this, it might have been from my dad at some point, but it's always stuck with me regarding team communication:
Repeat what you've heard to the speaker in your own words
This helps to build a mutual understanding of whatever the topic is (e.g. a new architecture approach, a design pattern, etc); a "yes" means you understand it and can describe it yourself while a "no" just means you need to continue the discussion.
What are some other "best practices" you've heard regarding communicating and working with teammates?