Listen!
When you are in any communication setting, particularly a high-stakes one, one thing that will give you an edge in the conversation is how well you listen.
I have tried this in different settings - personal, professional, and social life - that when you provide and create a space for other people, letting them talk while you just listen, you get to know a lot of information that you might otherwise miss if you are focusing more on talking.
Trust me; sometimes people even disclose secrets and off-the-record information that becomes vital to your overall communication strategy later. Try it and let me know in the comments if it worked out for you.