Haven't cruised in February, or on the Celebration, but there's a whole list of articles with tips for first-timers here.
As for ports, sit down and think about what you want to do in those ports. Do you want to go to the beach? Shop? Take an excursion? Carnival's list of available shore excursions can be found here.
Be sure to research, research, research!
I hope I helped some. Have a great anniversary cruise!