I am sure somebody has already thought of/mentioned this, but it’s new to me. I have some little, fine blonde hairs I’m having cleaned up by my electrologist. I can feel them, but they are very hard to see and remove. We tried some black follicle-enhancing goo, but that didn’t seem to help. So, I got a tube of cheap mascara and lightly ran the applicator over the area where I could feel the hairs. Lo and behold, they instantly became highly visible as though they had been dyed black. This made them very easy to see and remove, and the remaining mascara wiped off without a trace after my appointment. This seems to be a cheap, easy way to make removing hard to see little hairs a lot more efficient.
Hope this helps!