Get to the port by 11am. Theres enough to do to keep you occupied for 1 1/2 hours. The terminal is beautiful. Theres the model of the ship inside (to help you get oriented) and the real deal outside (to get you real excited). There are many soft couches and tv's showing Mickey cartoons. If you have children, my understanding is that you can register them for the kids clubs while waiting in the terminal.
They take embarkation photos - you will not want to wear clothes that clash with each other.
There is a embarkation lunch buffett up on deck 9 at Beach Blanket Buffett and the same one is inside on deck 3 in Parrot Cay.
Don't miss the manditory lifeboat drill at 4pm (and don't be late)
Read/Study the daily Personal Navigator - that gives you a list and times and places of all activities that are going on.
Don't try to do it all - because you can't!!
I feel that you don't have to worry about making ressies for dinner in Palo. Your rotational dinning is a lot of fun. Usually your servers are great and usually your tablemates are enjoyable too.
Skip the movies (unless they are doing a PremEar at Sea) because you can see them at home.
Don't miss the shows in the Walt Disney Theater because they are very good.
Try a lot of new foods at dinners. If you don't like the first choice, they are more than willing to bring you something else. Where else do you get to "experiment" on food for free.
There are shows between the dinner seating are very enjoyable. There are family "cabarette" shows in Wavebands and family game shows in Studio Sea.
Something I wish that we had done is send ourselves postcards for all the ports we visited (yes even Nassau). On
Castaway Cay you need real money to buy the stamps - your KTTW card won't work there.
Walk deck 4 or 10 at night. Enjoy the evening with your siginficant other. You'll be able to see passing ships and islands off in the distance.
Mostly...
Relax, Go with the Flow and Have Fun!!!