For mine, I was allowed the privilege of picking the board. It was rather conversational, with a veneer of formality. They asked me questions related to the courses I had taken, and rather broad questions. Don't be afraid to pontificate a little bit. There is really no way to be prepared totally- my impression was that they did not know which questions they were going to ask before they walked in, or only had a vague notion. If I had to do it again, I'd be a bit more confident than I was. I passed it the first time- I'd heard some people didn't - but I don't think I did anything special. Good luck with yours!