Begin Marking the Armscye
Measuring from the Front line of the draft, mark a point at 1/2 of the Front Shoulder-to-Shoulder measurement. Extend a line upwards from this point.
Do the same in back, using the Back Shoulder-to-Shoulder measurement.
Complete the armscye by drawing a U-shaped curve that connects the these two new lines. The curve should pass through the Armscye tick, but should never go lower. It may be asymmetrical.
Preparing for Straps
Add stubs for the straps. These will be lengthened later. On a person, I generally like the strap to be between 1"-2" wide. The strap width should be added away from the Side line.
Adjustment for a Large Bust
If you have a very exaggerated difference between your Bust and Waist measurements (and my doll would be about a 37 1/2″ Bust and a 21 1/4″ waist, which is pretty far fetched), you’ll have triangles that are proportionally quite large at the waist. This will lead to awkward angles in the next few steps. Here’s the work-around.
Divide the Front-most area of the block in half along the Bust line. Mark this with a vertical line. (Shown in pink.)
Divide the Front Triangle Base measurement in half. Using this new measurement, mark ticks to either side of the existing Front midline and the new front division. Draw lines from these ticks up to the intersect of the vertical lines and Bust line. (Pink)
By splitting the difference over two lines, we decrease the angle each will produce when folded out. Many small angles make up a curve, but one large angle simply makes an unattractive point.
Next: a little origami….