After applying, I was first contacted via email with the request to have a chat and discuss the position. I spoke with the HR rep later that day and at the end of the phone call she gave me and interview slot for a few days later. The interview was with three people and lasted about an hour and 10 minutes. If you have an interview, allow for extra time because my time slot was only a half hour. It was a relaxed interview where I felt very comfortable and was asked general questions about the job and my experience with different things. We did not get into schooling details or anything not directly related to what I will be doing in the new position. I was offered the job later on that same day.
My best recommendation is to just be yourself. The staff is very laid back and down to earth and they just want to know if you can do the job. No need to fuss with fancy clothes and going over and above to try to impress. Just bring your skills to the table and if you are the right person for the job you will get it.