General dirt, soft brush down, then wash with soap flakes, stubborn areas require gentle agitation with a soft brush.
Rinse clean leave to dry, if you have the green stuff on the roof, use Milton sterilizing fluid to get rid of it again rinse fully.
Once fully dry apply Ragg Topp waterproofer for Mohair top.
Vynil wash down with soapy water etc and dry off, use 303 aerospace protectant afterwards.