Attach what you wish to one end of the handle but use a stiff brush on the other end. I start with straight Chlorox in a small "yard-type" sprayer to kill the mildew (I'm sure that part of what is down in the non-skid is mildew). Scrub with brush and rinse. After rinsing the Chlorox wash/scrub with Simple Green. Works great. Of course with the Chlorox you need to be wary of its corrosive powers.