Even though I’ve been cruising for 18 years, I find packing for a cruise extra stressful. That’s because a cruise is many trips rolled into one, each requiring a different type of apparel for beach time, formal dinners, fitness, dancing at the ship’s bars and disco, and the many meals at onboard dining venues.

For a recent seven-night sailing on board Princess Cruises’ Star Princess, I whittled down my packing list to a capsule wardrobe , which made opening up the armoire in my stateroom and pulling out an outfit each day—or every few hours, as cruise itineraries really keep you busy—a breeze. I even had room left in my suitcase to squeeze in coffee beans and hot chocolate bought in the Dominican Republic.…