In order to remove mud, dirt, and to clean marks from the inner lining, Barbour recommend sponging with cold water only. Do not use soaps or detergents, as these will affect the performance of the wax finish. If detergent is used and damage is caused to the waxed surface, the jacket will not be weatherproof and any subsequent reproofing would not be possible. You can soak the jacket in water, as long as it is cold water only, no damage should be done. Once you have removed as much of the dirt as possible, the jacket should be hung outside on a clothesline to dry naturally. Do not put the jacket onto a direct heat source such as a radiator. Once dry, the jacket should be re waxed with Barbour Thornproof Wax Dressing (https://www.outdoorandcountry.co.uk/barbour-thornproof-dressing.html) to restore the weatherproofing.