This post may be a tad lengthy, but I think it’s important to get down the basic points of measurement all in one go. To measure a pose for drawing, here’s the steps:
1) Decide how much of the pose you want to draw. Here I’ve selected the entire length of the pose.
2) Hold a stick (a short cut of dowel rod will do) vertically out at arms’s length, against the pose. Place the top point of your selected drawing area (here the top of the head) at the tip of the stick. Wherever the bottom of your selection crosses the lower part of the stick, place your thumb. Hold on to that measurement carefully, and do not release your grip on the stick.
3) Turn the stick sideways and see how the length of the pose compares to the height. More often than you might suspect, major masses of the pose fit conveniently within the square measurement. You can see the remnants of my initial square for this drawing still on the page. For upright poses, you often get a 2 square long by 1 square wide grid. Draw the grid you find right on the page.
4) Now you must bisect the pose (and adjust the position of your thumb). Estimate half of the area’s total height, then check yourself. Repeat this process until you find a measurement with your thumb that is exactly half the height of the area you wish to draw. This gets easier and more intuitive with time. It is of particular importance when dealing with any amount of foreshortening. Often the center point of the pose will surprise you. Here I found the center to be the lowest rib, where the belly begins to turn in. I draw a line through my square and know that the edges of the pose must touch the edges of the box, and that the lowest rib must touch the mid-line. In addition, we have gained a valuable tool for the rest of the pose: a measurement of half the height. We can compare that measurement to other lengths within the pose, and judge distances abstractly in this manner. With so much information at our disposal, it is now much simpler to lay down correct structure.
Great advice for making quick, accurate measurements.