In my book Make Your Mark: Explore Your Creativity and Discover Your Inner Artist (Chronicle Books, 2004) (http://www.amazon.com/Make-Your-Mark-Creativity-Discover/dp/B0007ZNV1I/ref=sr_1_5?s=books&ie=UTF8&qid=1416922505&sr=1-5&keywords=make+your+mark) there is a chapter on Invisible Ink. You can paint with lemon juice, milk, and other substances, even Champagne, allow the paper … Continue reading