First, it’s best to clean the bag by hand, and dry it by air. (In an ironic twist, machine washing the bag damages its water resistance).
Fluff and light dirt can generally be brushed off if the bag is completely dry. If the dirt is too deep to be brushed, then you can remove it by following these instructions for cleaning Nylon fabric:
- Pretreat any stains by spraying a laundry-stain remover or dry-cleaning solvent on the stain. Allow it to soak into the fabric for at least an hour.
- Combine 8 oz. of warm water with 1 tbsp. of ableach-free and chlorine-free laundry detergent in a spray bottle. Swirl the bottle to mix.
- Spray the cleaning solution onto the bag. Use a soft- to medium-bristled cleaning brush to work the cleaning solution into the fabric.
- Dampen a soft cloth with cool water. Squeeze to remove excess moisture.
- Wipe down the item to remove soap residue.
- Air dry the bag.
That should fix ’er right up. For a more details, check out this blog post on how to clean your Minaal backpack.