Yesterday I started this drawing, and after I post this I will continue working on it. As you can see above, I began with a plumb line that hit the curve of the nose/eye/forehead area. It also lined up with a spot on the clothing, so it made for a good place to start my measurements.
As I continued along, I made measurements relative to the plumb line, and also relative to other points that had already been measured. The carpenter's rule of, 'measure twice, cut once,' is also applicable here as, ' measure twice, draw once.' Once I am sure of the marks along the plumb line, I use triangulation to place marks to either side of the line.
Of course, we all make mistakes. Once I got to the shoulder, I quickly found that I had grossly miscalculated the position of the gathered hair at the back of the head. Since I am double checking things at this stage, it is still relatively easy to correct.
In a day or two, I will have pictures to share from the Feminae opening. I had a great time, and thanks to everyone who made it out!