I have an interview at McDonald's

Girls, help me out!! I have a job interview at McDonald's today. It's only my 2nd job interview ever, and I really need to get this job. I applied at a job fair that was hiring teenagers so the manager is probably interviewing a lot of teenagers and I want to make sure that I get this job!! ANY tips? I know the basic, eye contact, firm handshake, smile and be respectful. Has anyone gotten an interview there and would like to share their experience? Or just tips in general? HELP!!