White is more difficult and if I had to mark a lot, I would buy the quilter’s water erasable blue pen. If it is straight lines, I use painter’s tape on the quilt top or my Hera marker. A Hera marker works best with the batt under the top and pressing firmly on a table or hard surface. If it is simple shapes, you can cut the shape out of freezer paper and iron it to the quilt top to quilt around.