Golf caps help keep the sun out of your eyes while playing 18 holes, or you can wear them simply for fashion.
If you wear golf caps on a hot summer day, they will most likely get filled with sweat and dirt. You can remove this by washing your golf cap, but it's important to do it safely, or it could lose shape and become unwearable.
Fill your sink with cool water. You want to make sure you're comfortable with the temperature.
Drop in about a third of a cup of laundry detergent. You can eyeball this amount if you don't want to measure.
Remove the cap from the solution and examine it.
Scrub any dirty areas using the old toothbrush. This can be done either under or outside the water.
Hang the cap so that it can air dry, which can take 24 hours. To speed the process, you can hang the golf cap out in the sun.