I like the soap idea. Is this your design? Our son and DDinlaw just told us that their theme for the baby's room is giraffes!
I love this one! I really like to back baste too, but have only used a light background so far. There are a few choices I have in my sewing room for marking on dark fabric. I usually use a chalk wheel but that is for machine quilting and does not last long. I also have Sewline brand mechanical pencil, You can get diff color 'lead' for it. Pretty small line. I also have a holder that takes soapstone or graphite. The soapstone is about the diameter of school chalk, but you sharpen it. The graphite is thinner. When you load it, you tighten it like you would a drill bit in a drill. I will see if I can get a picture of it. No company name anywhere to be found on it.