First you have a shop floor trial. They check if you are communicative and friendly. They will give you a product that you ahve to recommend. Try to ask open questions and appoach every customer. Don't just stand, move around, smile and keep busy. Then if you're succesfull you will be invited for an interview. very simple questions,like whatare your strenghts or weaknesses, give an example when you had to motivate someone staff like that.

I was invited to interview but ambushed with a group interview of 20 people. We had to split into groups and decide who we would kill out of a range of people. They watched us through a two way mirror. It was insane.