In the introduction to the third section of her book (the actual patterns), Giliarovskaia provides the following key:
“The drawings of the patterns are made according to a scale system. This is a system in which the pattern is drawn on the basis of chest measurements.
Divide one-half of the chest circumference by 48. The unit in the drawings corresponds to 1/48 of half of the chest circumference.
For an average figure (48 cm) the unit may be 1 centimeter. For other sizes, increase or decrease as necessary the measurement of the 1/48 of one-half of the chest circumference.
Drawing of the patterns always begins at the vertical line, the top of which is marked with the letter A.
Horizontal lines originate from the vertical line, to the right or to the left.” (page 64).
In other words, measure the chest of the person for whom the garment is intended, and divide by 96 (by 2 then by 48). Theoretically, the system works either in inches or in centimeters, but using centimeters provides more precise measurements. To create a pattern in the size you need, multiply the numbers provided in the master pattern by the personal unit you just obtained (1/96 of the chest circumference). Transfer the pattern to paper (I use banner paper or butcher paper, available in rolls of various widths at craft stores, office supply stores, or even in some grocery stores). Use the edge of the paper for the vertical line and mark the point A from which all vertical measurement will be taken. Then measure and connect the dots following the master pattern. If the garment extends both to the right and to the left of the vertical line, offset it as necessary. Essentially, you will be working from (x,y) coordinates, but from the top (right or left) instead of the bottom. Then create a mock-up in cheap fabric, fit as necessary, and finally transfer to the fabric chosen for the garment.
After you try it once, you will realize that it is really a simple and efficient system. And more importantly, a universal one, as it is based on individual measurements rather than arbitrary sizes.
Important note: the drawings are not to scale!
Do not attempt to enlarge the patterns and print them out! Transfer them to paper following the instructions! Otherwise you’ll end up with a fine mess!