Cruises can be a great way to see a small part of the world. For the most part you just relax and enjoy yourself while other people do the work. You can't go to wrong with that. However, the one thing you can go wrong with is what you pack for your cruise. It is one of the few things you are in charge of, so it is best to get it right so you can enjoy your cruise that much more.
The location makes all the difference for what to make. Most cruises go to a tropical locale, such as the Caribbean or Mexico, but others go to Alaska. If your destination is a warm one, bring shorts, T-shirts and loose-fitting clothing. You are going to be on the deck a lot, as well as on land, so you want to stay cool. For cold-weather cruises bring long pants (khaki are better than jeans because jeans don't block the wind as well), winter coat, gloves, hat, and any other cold weather article you would tend to wear.
Regardless of your destination, bring your swimming suit. There will be a pool (heated), and you may want to go swimming, and then maybe take a dip in the hot tub.
Business casual clothing is the appropriate attire for most meals on board.
Personal Hygiene Products
Bring your toothpaste, shampoo, soap and all other personal hygiene products with you. They will be available on the ship for purchase in case you forget anything or run out, but you will pay a price for the convenience. Bring plenty of sunscreen. A burn while sunbathing will ruin your cruise. Bring it even if your going on a cold-weather cruise, because your face will be exposed to the sun, and extra light reflecting off the water will increase the chance of burning.
Don't leave home without your driver's license and passport. When visiting foreign countries during your cruise you will need a passport to get onto the mainland or island. Without it, you'll be stuck on the ship.
Bring a small camera. Disposable cameras will be available on board as well as in the locations you visit, but they can become a burden to carry around after going through several of them, and, like everything else in tourist locations, they will be expensive.
Items for Shore Excursions
Do some research on the ports of call on your itinerary. Some of these locations don't have dependably clean drinking water, so you may want to take water purification tablets or bottled water when you get off the ship, depending on the location.
Small day packs make it easy to carry sunscreen and cameras on excursions.