Hi! I'm a current lifeguard cp. I work at the Contemporary. I'd be happy to answer any of your questions!
Expect check in day to be long. You'll be going through all the things all CPs do, but on top of it, you'll be doing your drug test and your swim test.
You'll have traditions in a few days after check in. Then you'll have a welcome to recreation class, 3 days of lifeguard training, and 3 days of OTJ training before you begin as a lifeguard on your own. I have way more information about this on my blog. Hope this helps!
My post on the first day:
http://kingdomhopping.blogspot.com/2012/09/check-in-day-aka-dehydration-station.html