Spirit asked for you to send in a resume and then from there you'll receive an email with an invitation to take a quiz regarding numbers and shapes (some of the questions don't make sense, I think that's the point). After that, you'll receive an invite regarding their hiring sessions. I went to the one in Fort Lauderdale. I'd say, be yourself but also be mindful that although it's a relaxed and fun airline they're also looking to see if you can follow directions and are a clear communicator. I would honestly describe the interview process being more like an American Idol audition based on the fact that you will be among a large group of people and everyone is very nervous.