I generally quadrant off the photo I work from, and the paper I'm working on, then I plot "x" and "y" co-ordinance
In other words, I measure, up and over, and, "plot" my picture. I'm left-handed, so I start in the upper right so
as not to smudge. I tend to feel obsessive, and uncomfortable once I've started a project until it's finished,
and tend to neglect important responsiblities like personal hygene.