Get some heavy embroidery thread--green, red or gold--and either do a stem stitch or a back stiteh down each of those lines. That won't add bulk and will be part of the design plan. If you don't want to do it by hand, choode one of the lovely designs you have on your sewing machine and sew down each mark. It's a lovely piece and I would be glad to have it and use it just as it is. froggyintexas