Here's what I do with the top:
Half of the time I wash it along with the car. I wash the top first using a shampoo made for canvas tops. I've used BMW, Porche, and RaggTopp shampoo. I like RaggTopp the best. I wet the top, then either spray the cleaner (RaggTopp, BMW), or mix the shampoo with water in a bucket (Porche). I use a regular large sponge to massage the top. I've tried brushes and sheep mits, but they leave bristles/hair imbedded in the top. Pain to remove. Anyway, after sponging, I rinse the top very well. I take a P21S drying towel and blot the whole top, which is almost completely dry after. Then I do the rest of the car.
Every 6 months or so, I apply a protectant. I like RaggTopp's protectant best, it seems to have excellent water repellency. I realized it was great when I went to wash it the following week. I could not get the water and soap to soak in at all. Applying is cumbersome. I partially open the top, then put newspaper at all the cracks, then lower the top on top of the newspaper to shield the rest of the car from the protectant spray. RaggTopp says you don't have to do this, and you can just wipe off overspray, but I did not find it easy, so I mask off everything.
Now, since the protectant works so well, I do not wash it everytime I wash the car. I just run over it with a lint collector (the ones that are sticky like masking tape) to remove any lint/fibers that have collected.
Hope this helps, let me know if you have any questions.
Brian