My favorite marking tool for stencils is the "Pounce" pad. It has two different types of chalk. A regular chalk that rubs off very easily. May not be good for FMQ on a domestic you will probably rub it off manipulating the quilt. Then they have the ultra pounce and the chalk can only be removed by washing or with a hot iron. I have never used the ultimate but have heard good things. One thing to keep in mind about Pounce pads, contrary to what the name implies, you do NOT pounce the pad over your stencil. You give the pad a good hard bang on a counter or other hard surface to load up the pad then you RUB it over your stencil like a chalkboard eraser. It is very easy to use and you can mark a large area very quickly.