Purchase a portable steam trunk with protective weather stripping on the inside of the door. This keeps the salty sea air from entering the wardrobe and staining your clothes.
Put your dresses and suits in dry-cleaning bags first. The bags will help protect your formal clothing if the portable wardrobe or suitcase accidentally lets moisture in.
Hang the clothes on the bar in the portable wardrobe. Take them out and double them up if the cloth gathers at the bottom of the portable wardrobe, to avoid wrinkles at the hems.
Place a sticker on the top of the wardrobe that reads, "This side up." When the workers load the wardrobe onto the cruise ship, this will prevent them from setting the wardrobe at an incorrect angle that will result in the wrinkling of your suits and dresses.
