Clean your bag in a large sink using a mild soapy, warm water and a sponge or soft brush. Treat your cover carefully, don’t use harsh chemicals and give it a scrub with a soft sponge. Once you’re happy that your bag is cleaned, you rinse thoroughly. Make sure you remove all traces of soap in and outside of your tube.
Finally, hang it out to dry outdoors or in a well-ventilated area out of direct sunlight. Your cover will both drip and air dry to finish up. Ventilation is the key to prevent it from being damp for too long.