Sewnoma

This is what I use too. I have a scrap of rough canvas that I usually use to wipe my mat down for quickie cleanups, but if I've been cutting a lot of batting and/or it's really stuck and/or my mat is just starting to show slices, I take it outside and give it a "scrubbing" with the nylon pad and then I hose it off and leave it flat on the wet grass (out of the sun) to slowly dry out (it's too big or I'd wash/soak it in the tub). Mine is an Alvin brand mat, not Olfa, but I think periodically wetting them down is good for all self-healing rotary cutting mats. I try to do mine once a year.