1 bottle of Light Karo Syurp, 3 drops of red food coloring 1 drop of green food coloring. Adjust color from there. You want it dark not bright. It's tasty (pure sugar) and safe to injest. Washes out easily from about anything but 100% polyester. Will wash out of 100% polyester if you do so while it is still damp. If you let it dry for a day or so then the red tends to tint the polyester.