I like to use this kind of textile ink.
It’s for screen printing, but I use it for all kinds of fabric crafts all of the time. By volume it’s cheaper than fabric paint, it’s a bit thicker (You can thin it with water if you want.), and lasts much longer. After it’s heat set it’s very colorfast. It’s also non-toxic. I buy mine when they are on sale or with a 40% off coupon at the craft stores.
*This was posted Via Jennifer Rizzo. com