Today's coat construction will be assembling the back of the jacket and sewing the shoulder and side seams.
Let's start on the back. Get pieces #5 (BACK YOKE) and #7 (JACKET BACK).
With right sides together, pin BACK YOKE (#5) to JACKET BACK (#7).
Stitch with 1/2" seams. Press seam allowances towards shoulder, topstitch (grading seams as necessary).
Staystitch the neckline of the back jacket with a 3/8" seam from raw edge.
Now, we will sew shoulder seams:
With right sides together, pin the FRONT JACKET PANELS to BACK JACKET PANEL at shoulders. **The front panels are shorter than the back right now, but it will all work out!
Stitch with a 1/2" seam allowance.
Press seams towards the back,
Grade seams and topstitch.
Repeat to complete both shoulders.
Let's wrap up today by sewing side seams.
Align and pin the two front jacket panels to the back jacket panel at the shoulders with right sides together.
Sew side seams with a 1/2" seam allowance. Repeat for 2 side.
Press seams open.
You basically have a vest at this point!