if my masks start to fog, I put a mixture of 40%-50% Babyshampoo (no special brand) and rest water into a tiny spray can. Works best... but these tiny cans where stolen sometimes. Now I printed a small sticker and pasted on it: "Muttis Spucke", means "Mommy's Spit"... the can lasts for two years now :-)... If I offer to others, sometimes I hear: That's not really true? ... answering with a long smile... before telling the ingrediants-secret....