It is very difficult to mark layers of sheers and synthetics with any kind of pen or pencil, because the layers ‘float’ on top of each other, and shift very slightly if you try to draw any kind of writing implement over the surface. For the lettering on my book pages, I’ve been using the tissue paper method. Not my invention, but a very useful technique, and one that I haven’t needed to use for many years.
Very simply, you write your words on a piece of tissue paper and tack (baste) it securely to your fabric:
Then you stitch (carefully!) right through the tissue into the fabric. I usually use split stitch for lettering.
When the stitching is complete, you can remove the tacking stitches and tear away the tissue, being careful not to pull so hard that you distort the stitches. You need to keep a pair of fine tweezers handy to pick out the tiny shreds of tissue that sometimes get lodged underneath the stitches.
Eighteenth century embroiderers used a similar technique for stitching onto velvet, using silk chiffon instead of tissue paper.