According to the CDC, the best way to store your cloth face mask depends on whether it’s dry or wet and/or dirty. Here’s a quick look at how to store your face mask in either situation.
How to store wet/dirty face masks
If sweat, spit, makeup, or anything else made your cloth face mask dirty or wet, then it’s a good idea to store it in a sealed plastic bag until you’re able to wash it. Wash a wet or dirty mask as soon as possible to minimize the chances of mold growth.
How to store dry masks
If you want to reuse a dry mask later during an outing, store it in a paper bag until you’re ready to re-wear it. (It’s helpful to keep a stash of paper bags in your car, purse, or briefcase.) A note of caution: Make sure you remove the mask properly by holding only the ear loops or ties and carefully folding the outer edges toward each other. Avoid touching any other part of the mask. Slide the mask into a paper bag using the ear loops or ties, and then wash your hands or use hand sanitizer immediately. When you’re ready to reuse the mask, pull it from the bag using the ear loops or ties, and make sure the same side faces out as did earlier. Wash your hands again after putting on the mask.
Per the CDC, you can store a clean, dry mask in a clean paper bag or mesh fabric bag until it’s ready for use. Mesh fabric bags also work well for this purpose. Infographic below
Infographic Source: https://www.quill.com/blog/lifestyle/how-to-clean-and-dry-face-masks.html