show up 15 minutes early. Better early than late. Better to overdress than to underdress for the interview. Expect to have others there applying for same position. Give the impression that you will be a long term addition to the company.
I agree with pickup, get the there early and overdress. When I had my interview I know I didn't need to but I wore my suit and they said they would call me 2-3 days later and the next day they called me and said I had the job.
All good advice (except for the suit part---do not wear a suit to your interview). Wear a nice pair of khakis and a polo shirt. Show up early. Don't hesitate when they ask you to breathe on the mirror and when they check your pulse.