Start by preparing all of your pattern pieces. You’ll need the back, the sleeves, two collar pieces, two front pieces, and two front facing pieces. Attach interfacing, add darts, pockets and whatever other stylistic things you want on the finished jacket.
Right sides facing, sew shoulder seams and side seams of front and back pieces
Pin collar with right side of the raw/unfinished opening to the right side of jacket neckline. Things won’t lay flat here, which is why pinning is so important. You’ll need to match center back, shoulder seams, and finally the edge of the collar to the notch of the jacket
Clip the open edge of the collar at the shoulder seams, remove the pins from the top piece of the collar. So now you have a little flap/opening.
Pin your front jacket facings to the jacket, right sides together
Sew from the lower hem line of the facing, up and around the lapel, across the shoulder seams, across the LOWER LAYER of the collar at the flap (leave the top layer unsewn, so the opening is intact, and then back down around the lapel to the other hem.
Turn the facing
Tuck the open flap of the collar under and edgestitch in place
So now you have this:
Finish the jacket. Hem
that just so happens to fit your son’s favorite stuffed toy perfectly.