I arrived about ten minutes early to the interview location, where I met the other candidates waiting in the lobby. Promptly at the scheduled time we were called in, our seats already having been assigned for us. Everything was laid out very clearly: The teaching sample was first, then the group activity, then a 30 minute informational session/Q&A with our interviewers. We signed up for our personal interview afterward.
In retrospect the teaching sample is the easiest part of the interview, yet the component I stressed over the most by far. I rehearsed for hours, and ultimately was slightly short on time because of a mishap with a bad marker (prepare for things like this). It was actually quite fun to participate in the other applicants' lessons, and the five minutes really flies by.
The group activity was much less intimidating than I expected. We were presented with two scenarios and had to come to a consensus of which route to take. Don't feel pressure to speak too much if you don't have anything useful to say, this component of the interview is really just meant to gauge how you work with other people and how solution-oriented you are. Take time to think about the situations thoroughly so that you can potentially propose the solution to the problem.
The personal interview was by far the most difficult part, clocking in at just over an hour for me. I was quite honestly caught off guard by the nature of the questions, and it didn't seem that my interviewer was satisfied with my answers as she kept pushing for more. Be honest, smile (but not too much), and most of all prepare for the role play scenario. I was praying that the interviewer wouldn't spring the role play on me as I'm horrible at roleplaying, but I was not so fortunate. Go along with it and try to take it as seriously as possible.
After that you're done. It was really less stressful than I expected, and the people were all very nice. Breath, rehearse, reflect on why you want to do this and you should be fine. If I can do it anyone can. I honestly thought I bombed the personal interview, but I still received an offer. Make of that what you will.