To prepare the front edge of the coat, we need two long strips (about 1 cm wide) of lining fabric, cut on bias.
On the lapel, baste the bias stripe onto the hair canvas (in the picture, the tape is placed on the edge of the hair canvas, but not basted yet).
Here you can see the finished front edge. The bias tape runs all the way down to the hem.
For the short edge at the lapel point you need a strip of the same lining fabric, but this time cut on grain. Baste, as well.
Before turning the lapel/facing right side out, you have to cut back the seam allowances, but gradedly. Also, make sure you remove enough of the fabric to allow the lapel point to turn properly.
This is, what my coat looks like after turning, ironing, and temporarily stitching the edge fast. This seam (which is clearly visible, running along the entire collar, in a lot of shots on the show) will be done with the machine once the pieces have hung out properly.