Want to prevent sweat stains? Try using a product like Sweat Stop Spray. The sweat should easily wipe off, creating less need for washing, and extend the life of your hat.
While we do not recommend washing hats, we know some of you sweat hard during workouts and would like to get those salt lines out of them. In most cases, a damp washcloth with a little laundry soap is enough.
If you feel you MUST do more cleaning, we have tried a hat cage (easily found on Amazon) and toss it on the top rack of the dishwasher (yes that's right! Please remove dishes prior to washing your hats). AIR DRY ONLY! Excessive heat WILL loosen the patch.
We added some links below for reference, but are in no way affiliates of Amazon or these brands.