I am a longarm quilter and use WASHABLE CRAYOLA MARKERS to mark my quilting designs. The only color I do not use is the black. I have had a problem getting the black to wash out in 1 washing. DO NOT IRON OVER THE WASHABLE MARKER. This can cause some "trace" to be left behind. i.e. You wash and the marker comes out but over time you see a shadow of the marker. I've been using the Crayola brand marker for years and the iron is the only problem I have encountered. I just buy the small 8 pack of colors which last for a very long time and they are not very expensive.