Number One - Your luggage may be several hours behind you to your cabin, pack a swim suit in your "carry on" so you can begin enjoying the ship facilities before your luggage arrives in your stateroom.
Number Two - The sun is bright, for those of us (mid 40s) only beginning to experience reading glasses, its tough out by the pool. Bring a book on tape or CD.
Number Three - Smuggle (in a lawful way) your own cokes/drinks on board. The cruise line rapes you on the price of beverages. I would love to find an "all inclusive" cruise line. This was the single biggest gripe I had and the single biggest I heard...$2.50 for a 12oz can of coke, $4.50 for a can of Bud Light, and $6.50 to $9.00 for a small mixed drink.... they could give you the cruise to get you on board to buy the drinks.
Number Four - a freebie - have fun, its the best vacation you will ever have
Crystal includes soft drinks and bottled water but not beer or mixed drinks, those are still extra. Supposedly Crystal is reducing its rates to become more competitive. I'm sure they will still be high and hope they don't have to sacrifice anything in the food or service area to accomplish this.