Several people have commented about markings showing through once quilted. I now use Frixion Ball Erasable Black Gel Pens by Pilot. After sewing (could be something as simple as a seam you've marked or an X on a square ora complex design), simply iron over it. The markings instantly, and I do mean instantly, disappear. Other colors are available, except, alas, white. These are available on Amazon. (Note: There is a similar Frixion pen by Pilot, but it is not the same as the one listed above, so be careful to get exactly this particuar one. I just love these pens!