|This is a short tutorial on my blog, describing how I attach the collar to the jacket in what I think is an easy and bulkless way.
A summary of what I do is below. Go here here, for the whole text and some pictures.
1) Sew the upper collar to the undercollar (my undercollar is cut on bias), stretching the trimmed undercollar to match the upper collar. Stop at the notches (marked with "stop here" on my drawing). Trim seam allowances if needed, turn, understitch and press. If you match the neckline seam on the uppercolar and undercollar, you will see that the uppercollar is bigger. Now fold that collar, still matching the neckline seams and put it around your neck. See now why the uppercollar is bigger? To adjust for the so called turn-of-cloth. The collar folds and rolls beautifully around your neck.
2) Sew the uppercollar to the facing (the collar's neckline seam to the facing neckline seam).
Trim, clip and press that seam open
3) Sew the undercollar to the jacket. Again, trim, clip, press open
4) Sew the facings to the jacket.
5) Now, fold your collar and put one seam allowance of the uppercollar and one seam allowance of the undercollar together (the other two seam allowances are inside the collar). Sew those seam allowances together, either by hand or by machine (using a zipper foot in this case). Turn and press. Isn't it beautiful? Light and without bulk.