It depends on the material, and you can tell by touch. Woven canvas and cushion fabric (you can see and feel the weave): mild soap and cold water; bleach only for mildew. Marine vinyl (smooth, coated face): mild soap and warm water; never a bleach soak, wax or fabric treatment. Clear vinyl windows: a gentle marine soap, a chamois or microfiber cloth, and a clear-vinyl protective polish; never paper towels, household glass cleaners or detergents. Mesh: mild soap applied with a cloth, rinsed thoroughly. Whatever you use, skip degreasers, and rinse until no soap is left.