Also buy one of those Mothers polishing ball, works great. My windows were very scratched and hazy and it made them nice and shiny again, although it didn't get alot of the scratches they still look 10 times better and I can see out of them.
As for the rest of the top I use a scrub brush and soap and water. Mud stains the fabric and you will end up with stains that don't quite come out.