Good luck, and remember that interviewers are always looking for what you can offer their company.
So, depending on the position you're looking for, think about the qualities you would expect to see in that position.

Are you hard working; well organized; reliable; good working with others; friendly and receptive to customers, especially when there's a problem; willing and open to learning new things, etc...?

They may also ask about where you expect to see yourself in the company in 5 years, so try to think ahead of time about the long term. Companies don't want to hire someone for 6 months. They want employees they can rely on for years, because the process of hiring and training new employees is never easy for them, either.

Also think about what in your schooling and life experiences qualify you for the positions you're looking for. I was once asked about a retail job I worked at, wanting to know the worst customer experience I had, and how I handled the situation.

Some places are worried about theft. I have no idea if they're still allowed to ask such things in today's PC culture, but for a warehouse job years ago, I was once asked if I had a criminal record, and if they checked with the police, they would not find any arrest records.

Basically, just be prepared for anything, and be honest and yourself.