They get you to sign some paperwork/fill out preferences and whatnot. Then you write your name on a sticky label, they asked us to draw something meaningful to us, then asked us about it. They split you up into groups of four, and have you do activities with the other 3, then with a partner. Um, from memory, not a lot of it was based on customers, there was like.. what would you do in <insert situation here> that you had to do with partner, general store situations.
It could be entirely different now, I went for my interview a bit over a year ago. But yeah, it's not hard, I found it relatively enjoyable.