Grid Lines
Sharon, my drawing teacher at the Royal Drawing School, only lets us do horizontal and vertical measurements, we're not allowed to measure angles directly or do "how many heads in a body"-type comparisons. Sometimes I do sneak in a forbidden measurement when she's not looking but for the most part, I try to follow her rules. This is because I'm concerned about forming bad habits. I have to say though, it's not easy sticking to these limited ways of measuring, especially when judging the size of something which is often hard to compare to other elements of the drawing.
One thing I experimented with last Friday was to draw out the grid lines I measure on my drawing surface. This forces me to continually compare and relate all the parts of the face or figure. I'll play around more with this idea next Friday or whenever I draw next.
On that topic: the project at work that has kept me busy for the last weeks has reached its conclusion so you can expect a more regular cadence of posts on here starting this week.