On the form, measure the length of the muslin from the shoulder over the bust to the waist along the selvedge edge.
Add about 4" to this measurement.
Clip through the selvedge
Tear the muslin
On the form, measure the front width across the bust arc along the crossgrain (top edge of the muslin) from the center front to the sideseam. Add four inches, clip, and tear as before.
Draw a grainline on the front piece 1" from the longest torn edge.
Measure and mark 4" down from the top. Put a second mark at the bust level. Measure the form for this distance.
Draw a line with the L ruler from the bust point.
Measure, tear and prepare a piece of muslin for the back. Measure and mark 2" down from the top edge. Make a second mark and draw a crossgrain line at the shoulder level.
Fold the front muslin piece along the grainline you drew and crease with your finger.
Pin fold to the form, with the crossgrain line at the bustline. Place your top pin pointing down, and your bottom pin pointing up so the muslin does not slip. Place crossed pins at the bustline level.
Smooth the muslin keeping the crossgrain parallel to the floor and place crossed pins at the bust point. 
Smooth muslin upwards from the breast to the middle of the shoulder and pin.
Smooth the muslin up to the shoulder/neck intersection. Slash the shoulder seam about 1" away from the neck.
Trim muslin at the neck down to about 1" from the neck seam.
Smooth the muslin upwards and clip the neckline by placing the point of the scissors on the neck seam.
Then fold the fabric above the seam into the scissors.
Then close the scissors. Be careful not to let the muslin under the point of the scissors slip.
Continue clipping the neckling at about 3/4" intervals. Pin the shoulder at the neck.
Pin the Shoulder Point
Starting at the shoulder tip, smooth the muslin along the armhole roll line towards the midshoulder pinhead. The fabric should bridge the hollow area between the shoulder and bust.
Trim the waist
Smooth and slash the muslin along the waist toward the Princess line using the same clipping technique as at the neck.
Pin the waist at the princess line 
Mark the waist at this location for the dart 
Mark the following:
- bust point
- 3/8" below CF neck
- mid-neckline curve
- shoulder/neck intersection
- shoulder tip
- mid-armhole mark
- CF at bottom of waist tape
Lift the muslin at the armeye. Direct a 1/4" easetuck toward the bust and pin. Cut away excess fabric at the armeye.
Smooth the muslin around the armhole and pin just past the side seam
Place a pin at the bottom of the armhole plate. Smooth the muslin down along the sideseam to the bottom of the waist tape and pin.
Pencil rub the sideseam
Remove pin from the easetuck at the armeye.
At the bottom of the armhole plate, draw a short curved line. Draw a line down to the pinhead marking the armhole depth. Draw a second horizontal line here.
Measure 1/2" for sideseam ease.
Draw the sideseam with a ruler, connecting to the bottom of the sideseam at the waist. There is no ease at the waist.
Mark the bottom of the sideseam.
Slash along the waist from the sideseam to the princess line.
Pin a 1/4" ease tuck at waist
Fold the dart excess towards the center-front. If this excess overlaps the centerline, trim it to within 1" of the dart legs. Mark at the princess line.
Bring the first dart mark you made to this mark. Crease-fold the excess fabric of the dart inward. 
Place the pins perpendicular to the foldline of the dart legs.
Do not pin through to the form.
Fold and crease the shoulder seam and side seam under following the guide marks. Peel back these seams and pin.
Fold and crease the muslin for the back drape and pin to the center back seam of the form at the neck, shoulder level, and waist.
Smooth the muslin along the crossgrain from the center of the back to the pinhead of the mid-armhole (keeping the crossgrain line parallel to the form) and pin.
Smooth the muslin upwards and trim and slash along the neckline.
Pin the shoulder at the neck
Smooth the muslin along the shoulder towards the Princess line, and mark the intersection of the princess seam and the shoulder seam
Mark the dart intake 1/2" toward the shoulder 
Draw a 3" line along the princess seam to direct the angle of the dart
Slash to the shoulder seam about 1" from the neck
Fold the muslin along the 3" line down to meet the dart intake mark, folding the excess toward the centerline. 
Pin the layers of the dart together, placing pins perpendicular to fold, but do not pin the form
Smooth the muslin to the shoulder tip, then mark and pin the shoulder point
Run your finger along the roll line of the armhole to the crossgrain pin to test the smoothness. If loose or tight, release the pin to adjust.
Mark the armeye
Trim and clip the waistline to the princess seam. Mark for dart.
Mark 1.5" (1" for juniors) from the Princess line for the dart intake
Fold the waist dart from the crossmark to the dart intake mark with excess towards the centerline. Place the pins perpendicular to the foldline, but do not pin the form.
Smooth, trim, and clip the muslin along the waist.
Pin a 1/4" ease tuck. Continue to smooth and slash the muslin along the waist. Pin at the side seam.
Pencil rub, measure and draw side seam as for front, but with 3/4" ease
Mark back waist
Release holding pins. Carefully match the guide marks of the front shoulder seam and side seam over the back seams. Pin the seams perpendicular to the foldlines, but do not pin to the form.
Remove holding pins and check the armeye, center front, and center back for any pulling or twisting.
Mark any corrections needed with a red pen. 