I use black thread. As far as finishing the head with eyes, once I have completed my whip finish and cut the thread bobbin off I coat the head with Sally Hansen to seal it and then put the white spot on using fabric paint. Once it is dry, a couple minutes, I put either a dot of red or black in the center and let it dry. After it has had a couple of minutes to dry, I re-coat the entire head with Sally Hansen which really makes the eye part stand out better. The reason I coat the thread head before making the eye is to seal the thread so the fabric paint does not sink into the thread and spread out. I purchase the fabric paint from my local Wally World. It comes in many colors and in a 1 oz squeeze tube. Goes a long way and is waterproof. I figure if it can stand the washing machine in clothes, it should stay on a fly head while fishing.
You have an open invitation to come fish when you can. I am thinking about spending 3-4 days in Townsend, TN during the first week of September to fish the Little River and some of the mountain streams.
Fly fishing and fly tying are two things that I do, and when I am doing them, they are the only 2 things I think about. They clear my mind.