Whether you're enlisted, attending a costume party or just really driving home the nautical look, you'll find the classic U.S. Navy sailor hat a simple item to care for, as this cup-style cap is typically made from 100-percent cotton twill. Not only does heavy cotton offer a balance between ruggedness and breathability, it means that you can care for the cap with standard laundering methods, including using household items to remove stains and tossing the hat in the washer for quick cleaning.
Turn the brim of the hat down before washing. This allows access to all of the cap's folds and crevices, where dirt and stains often lie.
Apply a pretreatment of undiluted white distilled vinegar directly to any day-to-day stains on the hat, dampening the blemishes thoroughly. Vinegar cuts through many common stains, including tough ones, such as wine, fruit juice and cola, as well as discoloration caused by sweat.
Soak the cap in a bleach solution, as an alternative to the vinegar treatment, if it's discolored or heavily stained. Fill a bleach-safe container with a gallon of clean water and mix in ¼ cup of household bleach. Submerge the hat in the solution and allow it to soak for about five to 10 minutes.
Wash the hat in your washing machine, set to a regular warm water cycle. Add regular laundry detergent in the amount recommended by the detergent's manufacturer and about ¾ cup of household bleach, then let the cycle run its course.
Allow the hat to air-dry thoroughly. Ensure that it is completely dry before folding the brim back up and storing it in a cool, dry place away from direct sunlight. Otherwise, you risk acidic degradation, discoloration and the formation of mildew on the cotton material.