Silk taffeta dress WIP, the contrasting green neck edge. Tip 1: pieces like this are more stable and easier to handle if you don't cut out the hole in the middle until after stitching it onto the main piece (i.e. here, the dress). Tip 2: to avoid a skewed, asymmetrical end result, sew each side to the center and stop there, flipping to the other side after the first side is done. That way, it's the same movement, same curve, you're making on both sides. After stitching it to the dress, trimming/clipping seam allowances, and pressing to the outside, it was edge stitched down. I used a thread from the green silk to edge stitch it for perfect color match. I had pulled the thread earlier anyway, to find the straight of grain a cut even bands of the fabric for trimming.