Check the care label
Test for colorfastness on a hidden spot
Remove loose dirt with a soft brush
Fill a basin with cool or lukewarm water
Add a small amount of mild detergent
Submerge the hat and gently swish it
Spot-clean stains with a soft cloth or toothbrush
Rinse thoroughly with cool water
Press out excess water with a towel
Reshape the hat
Air-dry away from direct heat or sunlight
Avoid machine drying unless the care label allows it