Cruise lines do not have any restrictions on the amount of luggage you bring on-board.  However, if you're traveling to your port of departure by plane, the airline may have restrictions.

Pack for a cruise like you would pack for any resort vacation.  You'll spend most of your time in casual attire...during the day and while at ports of call.  Determine the appropriate casual attire based on the weather for the time of year and cruise destination.   Review Dress Codes to determine the appropriate attire to pack for dinner in the ship's dining room or any special shipboard activities.

If you're planning on any specific shore excursions, consider any special attire you might need, like hiking boots, ponchos, or rain gear.  If you plan to snorkel and have your own snorkel equipment, you might want to bring it along.

It's a good idea to pack all of your medications in a carry-on bag that you'll keep with you.

Take a lesson from experienced cruisers and include anything you need for your first day aboard the ship in your carry-on bag.  Sometimes it takes a long time for your luggage to be delivered to your stateroom, so if you want to plunge into the pool as soon as you board the ship, or change from travel attire to cruise wear,  you'll want to pack the appropriate clothes and other essentials in a carry-on bag.  

If you're cruising to a warm, sunny destination, don't forget your sunscreen.  Nothing will ruin a vacation like a bad sunburn!  

Almost everyone will want to bring a camera (with extra batteries) to capture the fun on their cruise vacation.

Most ships are equipped with 110-volt electrical outlets in every cabin to accommodate electric shavers and other personal appliances.  Hairdryers are included in the staterooms of almost all of the modern ships, so you probably don't have to pack one.

Be sure to leave some space in your suitcase to bring home some treasures that you might find along your journey!

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