[CHAT] How to draw my own wash-out pattern?

I have a friend who wants to do a pre-printed or "stamped" pattern that you wash out when you're done, but is having a hard time finding a design that they like. I thought for a present I would buy a pattern and make them their own kit by drawing it on fabric for them, but I'm not sure what materials to use. What type of pen should I get? And can I draw on regular Aida fabric, or do the wash-away kits use a special kind?