Cruises are a paradox of packing. Swimwear, casual clothing, dinner dress, and even formal clothing are needed for a week at sea, but passengers are expected to fit all of this clothing (up to four people) in a stateroom the size of a walk-in closet. Here are five tips to help you bring everything you need without going overboard.

Wear everything twice

Most cruise passengers wear at least two outfits per day, for daytime and evening. If you are only going to wear an outfit for a few hours, there is no reason you can't mix-and-match the same pieces two or three times during the trip. Laundry facilities are available on some ships, or bring a travel-sized fabric deodorizer or detergent for quick freshening or sink washing, if needed.

Here are the basics for a 7-night warm weather cruise.

• 2 swimsuits

• 1-2 swimsuit cover-ups

• 1 formal outfit (suit and tie for men, nice dress for women)

• 2 slacks or skirts in neutral colors for non-formal dinners

• 3 dress shirts or tops for non-formal dinners

• 3-4 casual daytime outfits

• 1 sweater or jacket

• 1-2 sets of workout clothing (if you honestly expect to use them)

• Underwear for the entire trip

• Shoes for walking, the beach and formal. Bring as few as possible.

• Accessories

For a cruise in colder weather, like Alaska, you may need only one swimsuit, but more sweaters or other layers. If you are planning a hiking excursion in the jungle, pack appropriate clothing and footwear. Formal night and dressing for dinner are optional on many cruise lines, if you don't mind eating at the buffet instead of the main dining room. Consider your destinations and preferences and pack what you need, but plan for your clothing to do double or triple duty as often as possible. You'll need that extra space to bring home souvenirs.

Light, wrinkle-free fabrics

Polyester blends, rayon, and spandex knits won't wrinkle and take almost no space in a suitcase. Choose low-maintenance, breathable, and comfortable clothing and leave everything else at home.

Take only as much luggage as you can personally carry

Make your life easier, and less expensive, by limiting your luggage to one suitcase and one carry-on. Fewer bags mean fewer airline fees and less potential for lost luggage. Your stateroom will look less cluttered if you have fewer bags to store. You may have the option to exit the ship quicker at the end of your cruise if you can walk off with all your bags rather than waiting for your assigned time to search for your luggage at the port.

Pack a swimsuit and cover-up, a dinner outfit and a casual outfit in your carry-on, along with prescriptions, toiletries, sunscreen, camera and whatever else you feel is essential. In the unlikely event that an airline loses your luggage, or you're ready to try the pool or go to dinner before your luggage is delivered to your room, you'll be glad you did.

Details, Details

On our first Caribbean cruise, I packed a single can of spray sunscreen and it was used up on the first day. The tropical sun was so intense, we had no choice but to purchase sunscreen in the ship's gift shop for twice the amount we would have paid at home. Here are other items to consider packing:

• Plenty of sunscreen

• Ibuprofen and other medications you may need

• Camera, with extra batteries and memory card

• Waterproof pouch with belt to hold passports and money at the beach

• Binoculars

• Sun hat

• Personal electronics (e-reader, MP3 player, cell phone, tablet...)

• Chargers for personal electronics

• Reading material for beach

• Snacks, such as trail mix, individually bagged for the airport and when you're in port

• Ziploc bags and plastic grocery bags to separate wet things from dry

• Backpack or beach bag to tote what you need in port

• Extra hangers - especially if more than two in a room

What not to bring

• Beach towels. The cruise line provides these for the pool and beach.

• Denim. It's too hot and stiff, especially on tropical cruises.

• Bathrobes. Many cruise lines provide these in the cabins.

Cruises are even more fun when you know what to expect and come prepared.