there are tons of options on the market for marking your quilts---no matter what you decide to try always test first to make sure it will come out- some come out of one quilt then not the next so each time you should test to be sure it is going to come out- but everyone has some they have good success with and ones that they have problems with- personally i 98% of the time use a mechanical pencil or chalk- although i have used blue water disappearing ones, frixon ones you make disappear with an iron (or heat)