For the women, cocktail dress, gown or hostess skirts, etc. Many ships also have Passenger Talent Shows, so don't forget your sheet music, kazoo, or tap shoes if you think you'll want to participate. Your cabin does not have a clock and even though most ships do have wake up services, you might want the clock for general knowledge of time. Most contemporary cruise ship libraries are limited in content and shipboard boutiques stock the same types of books you'd find at the airport. Laundry takes a bit longer aboard ship than in a hotel, and neither laundry nor pressing are accepted toward the end of the cruise.
Some ships have dry cleaning facilities.
Based upon a 7 day cruise. For longer cruises, plan accordingly. Don't entrust them to anyone to carry for you. Include the Cruise line, the ship, your cabin number and your flight schedule. It's the best identification you have.