If the boat is very dirty with road grime I use Tide clothes washing detergent, because it cuts grease very well.

If it's just a little dirty, I use Ivory dish washing liquid. When it's dry I polish it with that Teflon wax stuff, and yes, it makes it very slipery and hard to climb up on it after a crash or even when you are trying to trap and miss the non-skid part. I also spray every moving part (blocks, traveler, self tacker, etc.) with Team McLube teflon spray before racing.