Divers have tried a lot of ways to clean their slate or wetnotes:
kitchen cleansers, as well as toothpaste and sandpaper, but they all pretty much make a mess and are not very handy. A much better alternative solution to cleaning carbon pencil from your slate is melamine foam, sold in the US as Mr. Clean® Magic Eraser. It looks like a small sponge, and is not abrasive or soapy. You can get a box of them in any grocery store, and to make them last longer simply cut each sponge in half. To quickly remove your carbon pencil notes just wet it and wipe, and we aren't talking elbow grease... just wipe. It works great and there is no soapy residue, so you can just throw them in your dive bag or dry box.
