Page 31 of Andrew Loomis's "Figure Drawing for All It's Worth" has some more helpful diagrams.
Oddly, the top diagrams on this page shows the finished drawing before the guide lines. It makes more sense to start with the last drawing and work your way to the finished drawing so that's how I'm going to show it (click on images to see them larger). Also, it looks like Loomis drew the guide lines freehand but I recommend that you use a ruler for accuracy.
1. Start by establishing an horizon line (the eye line of the viewer).
2. Choose a height for your figure with a vertical line, imagining that it extends from the top of the figure's head to the bottom of his feet.
3. Choose the depth of the perspective for the figure by drawing lines from the top and bottom of the height line to the same spot on the horizon, the vanishing point (shown here in red.)
4. Using Loomis's 8 heads proportion, divide the height line into 8 equal sections. To maintain accuracy in your divisions, it's important to make your divisions on the straight, vertical line since it is not in perspective and therefore not distorted (the lines are shown extended to the vanishing point.) Loomis added some additional lines: the blue line is for the shoulders; the green line is half the distance between the head and the bottom of the knees.
5. Draw another vertical indicating the width of the figure. For a male, Loomis uses a width of 2 1/3 heads (for a female, the width is 2 heads.)
6. Draw diagonals in the box to find the correct center in perspective (shown here in yellow.)
That's the completion of the "Quick Set up of the Map." Once you have this, you can place the figure in it using the landmarks on the body creating the "Quick Set up in Perspective."
If you like this post, please become a follower of my blog by clicking under the "You" section on the right. Thanks!