I tried to find out as much as possible about the company, position and most importantly interviewer. Tried to develop some talking points early on where I shift the focus away from me and onto the company or interviewer. Most people love to talk about themselves. Better than talking about yourself is putting transitions in where you get to tell the person who is talking to you how great they are.
The interviewer really doesn't want to be there. The sooner you can transition the interviewer from the interrogator to the friendly conversation, the easier the interview will go. Most people, and no different for interviewers, want to hire people similar to them. If you can find out what they like to do or accomplishments they're proud of and redirect the focus to that, the sooner you can get over the awkwardness of the interview and they become less stressful.
I've had interviews where we spent 1-2 questions talking about me and the rest on a mutual interest, the company or the interviewer. Clock runs out and the interviewer tells me what a great interview it's been. Of course it was. We spent 2 minutes talking about me and 28 about what a cool dude you are.