Hi Wonderly, is this where you are?
4. Keeping the edges of the outer yoke folded, align and pin it to the yoke lining (the unfolded yoke) with right sides together. Stitch the neckline and the sleeve edges with a 1/2″ seam, backstitching or lockstitching at both ends. [LG adds: this is where you’re sewing the two yokes together at ONLY the neckline and the sleeve edges. Leave the top and bottom of the yokes open so they can be attached to the dress itself in the next steps.]
5. Trim the stitched seam allowances to 1/4″. Turn the yoke right-side out and finger-press the edges, rolling the seams slightly toward the inside (the yoke without the folded seam allowances). Press the stitched edges with an iron to finish them.
I’m attaching two photos that may help? They weren’t meant for sharing so they’re sewn with navy fabric, which isn’t the easiest to see. Maybe this will help? I’ll check in again soon to see where you are.