Hi Techmike
use only luke warm water and PH neutral soap like Ivory or Dove soap bars. take a soft bristle brush and clean the top with the grain gently. the softer you clean your top the longer it lasts. If you need Water proofing try to get "Aqua-tite" it is a professional Water repellant used in the Marine industry to water proof canvas. In Canada you can"t buy it over the counter, toxic to inhale..... and do not get it on the plastic window!!! It needs about an hour drying time.