1) There is a lunch onboard on embarkation day - it is open from the time you board until 3pm or so.
2) The terminal is a nice place to wait to board the ship. You get to look at the model of the ship inside and look at the real deal outside. There are characters for pictures/autographs and cartoons on the tv's.
3) Try and arrive around 11am - 'tis better to wait in line "outside" (in the terminal) than to wait in lines inside (on the ship) - if you want spa or palo ressies or have children to sign into the kids clubs.
4) You can't do it all - so don't stress out over it and don't try to do it all. Therefore be prepared to make some difficult choices
5) You can't eat it all either. For me personally, I like the breakfast buffett and the dinners (especially the desserts). I generally skip lunch - just grab some fruit and chocolate chip cookes from Scoops for an afternoon snack to hold you over to dinner time.
6) the Navigator you receive in the terminal is a "highlights" navigator. The one in your room (or at guest services) that you get upon boarding is complete. Check them both over carefully. (bring a highlighter to mark the items in your navigator that you are interested in doing)
7) Take the stairs!! Usually much quicker than waiting for an elevator AND you get to eat more dessert at dinner because you worked off some of the food from prior meals.
8) Don't worry about eating in Palo. Yes the food is better there (the food is very good in the main restaurants!!). But its not worth stressing over if you don't get the ressie. We enjoy making new friends - our tablemates for the duration of the cruise and the wait staff (I've always enjoyed our room stewards too!). So we have chosen NOT to eat dinner at Palo. We do eat brunch in Palo - Awesome!
9) Forget about sleep - that's for after the cruise

!!! We usually got to bed around midnight (sometimes a little earlier sometimes later) and tried to get up by 7am. 7 is usually to late to catch a sunrise - and you should try and catch at least one of those while onboard - along with the sunsets!! One of the other things we do at least once per trip is to watch the captain dock the ship. I have a hard time parallel parking my car, let along a 975 foot long ship!
10) Relax and have a great trip. Don't stress the little things and remember most of the stuff you may have to deal with ARE little things. Enjoy your family. Enjoy the crew (treat them with kindness and respect and they WILL go out of their way for you!) If changes happen to your ittenerary - oh well - go with the flow. The only exception to this that comes to my mind is if your flight schedule gets changed and you have the possibility of missing the ship - then panic and get snarly with the airlines. This leads to my last point...
11) Fly in at least the day before your cruise is scheduled to leave. Remember the "boat" waits for no one. This applies to embarkation day and any stops in port. Also, Remember to change your watches any time
DCL tells you that they will be changing their time. DCL ship time IS local time in port. NEVER miss the ship!!!
Have fun!