Add about a teaspoon of baking soda to a small cup, then a squeeze of lemon which will make the baking soda bubble (hee, hee, pretty cool), then add water. I take a rag, dip it in the concoction and wipe the mat down thoroughly. Then I rinse out the rag, keep it damp and wipe it down again with just water. Then I let it air dry in the shade or in the house