ok my mistake i got it slightly wrong but here you go guys

cleaning it

vinyl just use warm water and plain soap make sure there no wax in it or it will make the vinyl brittle and then crack so just use washing up and warm water and soft scrubbing brush then risin with clean water

waterproofing and keeping it shiny and help to protect it from going brittle

believe it or not, wd40 will do it, spray it on lightly, buff in with a new shoe shine brush, then wipe the excess off with a cloth, hey presto, nice shiny waterproof roof,

hope this helps