It is not necessary to remove existing nonskid. Just follow the product instructions. Clean with degreaser type product, like simple green. Usa a stainless steel wire brush for the hard areas. Tape off area, hand sand to rough up surface, wipe down dust, finish up with tack cloth.... then start your application. Plenty of youtube stuff, plus the website has instructional vids. This product is not designed to restore existing non skid. It is an entirely new surface.has anyone used Kiwi non skid just courious if they sanded first