Feeling prepared is really key. Something that really helped me is also preparing some phrases to fall back on if you feel like you're spiraling.

For example, if you feel like a question puts you on your heels a bit, you can give yourself some breathing room by saying, "Let me think on that for a second." It can help you alleviate that "oh god, I'm not talking and they're not talking and I'm taking too long to answer, maybe I should just blurt something out but I don't want to say the wrong thing" anxiety. You come across as contemplative and it helps keep some of those intrusive thoughts out of your mind while you put a more thoughtful answer together.