From my experience I would suggest the following:

A complete and thorough reflection of WHY an MBA would help you achieve your career goals. Know very well what you wrote in your essays and make sure that you reinforce it in the interview.

WHY MBA? WHY MBA NOW? CAREER GOALS?  ABOUT YOURSELF? (Hint: Show a career progression and also showcase extra curricular activities) WHY XYZ SCHOOL? (Hint: Bring out the match between your goals and what the school has to offer and also what you can contribute and how you can continue to pursue your other interests.) These are all  typical questions and they must be answered VERY VERY well.