Time for the collar! The trickiest part after the darts, (but not actually that tricky, just some precision) and full of valuable skills for your garment sewing). The top of a collar (the part that shows) is called an uppercollar, and the underside is called the undercollar. I'll be using these terms throughout. Optional couture tip: When cutting out your undercollar, make it 1/8" shorter on 3 sides (you can leave the side that goes into the neck alone). When you turn the collar rightside out, having the undercollar be just a wee bit shorter will help roll the seam lines underneath so you can't see the undercollar at all when wearing the garment. Interface the uppercollar. I prefer a woven fusible interfacing (like this). I don't recommend the non-woven stuff that feels like paper - that stuff is better for crafts (and masks!) than garments. No, your interfacing should not dip down in the center like this. I'm just running really low and didn't have any wide enough. I didn't want a contrast on my uppercollar, but if you want that sew it on now. press your seam allowance underneath pin or hand baste (I recommend by hand for extreme precision!) it on the uppercollar sew it on either right at the edge by machine, or a prick stitch by hand. Sew your uppercollar and undercollar right sides together. If you made the undercollar 1/8" shorter on the sides, just barely ease your uppercollar in. You want this to match at the edges. If you have a clapper, use that to press open the seam allowance. If you don't, roll up a towel and shove it in and do your best. That's where the seam allowance are going to end up, so you want to help them get there! Example: Trim off the corners close to but not through your stitching. Trim the undercollar seam allowance so it is shorter than the uppercollar. (You always want the longer seam allowance to end up on top, so you are less likely to see a ridge in the finished garment). Example: Flip the collar rightside out! Use something to push the corners out as far as you can to make them square. Don't use scissors, they will just poke through (ask me how I know this ) A tapestry needle or knitting needle works well for this. Press the collar flat! You want to have the seams right at the edge, and not rolled towards each other which can be a bit tricky (and cause finger burning to get them out) but this will help your collar look crisp and square. Woo we are so close to done at this point! Just need to attach the halves together. Pat yourself on the back because the finish line is in sight!