@nyukellogg2015
First off, congrats on the interview! That's half the battle. As for interview tips, I think the most important thing is to just be yourself. That being said, here are a couple of things to note:
1) Do not get thrown off if the interviewer has someone else present in the room with them during the interview. They do this to help with training. Just stay calm and make eye contact with both of them, don't ignore the other person. They may be judging you. This happened to me at Stern and it happened to a friend of mine at another school as well. I do think though that it's probably more common early on in the admissions cycle.
2) Do not overprepare. I made flashcards of all the questions on ClearAdmit with bullet points of my answers. I think it's good practice to do this and have an idea of what you want to say. However, don't go overboard in reviewing this stuff. I think I ran through the flashcards just once right before the interview. You don't want to sound rehearsed.
My experience was probably fairly typical (minus the other person in the room). Oh and the fact that they called me in about 15 minutes after my scheduled time! They really didn't ask any questions that were not already mentioned in ClearAdmit.
Hope this helps! Good luck!