well not much to add....just have fun.
get to the pier early if you can...it's nice to be able to orient yourself to the ship before the majority of passengers show up.
while there is no "dress" requirement for the 1st dinner, well....you do have to BE dressed....clothes are preferable to a birthday suit! (sorry, couldn't resist!)
you only have to do 2 things....the boat drill and, well, they make you get off at the end of the cruise, which i think is pretty rude! i mean, why can't you stay??!?!?! OH YEAH, and you can NOT bring home your cabin attendant and/or waiters in your suitcase either! the nerve!
Have a great time!!!!!