The best way to keep your vinyl looking new is to keep it covered and clean it regularly with a mild soapy water solution, followed by a thorough rinsing. Then follow up with a UV protection product. This should be done monthly.
Because the seams of your exterior cushions are not waterproof, you should store them in the cabin or cover when not in use. This will also prevent moisture being trapped between the cushion and the gel coat which could result in blistering of the gel coat.
Sometimes, despite ongoing efforts to maintain the look of your cushions, your vinyl may need more than a routine cleaning. In those cases, start with a soapy water washdown. This will remove sunscreen and general dirt. Then apply a commercial cleaner marketed specifically for vinyl products.
Remember that while vinyl is a tough, durable material, using strong cleaners that contain bleach or ammonia can break down the vinyl over time, so it’s a good idea to avoid such products.
For further information refer to your owner’s manual.