You can also use 100% silicon caulk to make a non-skid pattern mold with...it has the added benefit of being flexible so you can apply that pattern to other areas of the boat that aren't necessarily the same shape as the area you made the mold from. You'll need some sort of mold release to get the silicon to remove cleanly...can't recall what the right stuff is at the moment, though. I'm sure the internet can help.


Edit...welp, here you go: http://www.martha.net/2014/05/making-a-100-silicone-caulk-mold/