How to do the chemise side-seam:
1.Pin RIGHT SIDES together
2. From the INSIDE baste the raw edges for the side seam back 1 cm or 3/8” between the hem and the sleeve opening.
3. Whipstitch seam from the INSIDE.
4. Take out basting and press the seam allowances in the same direction away from the body of the garment.
5. Trim the only top seam allowance down to half the width.
6. Baste the non-trimmed side over top of the trimmed seam allowance.
7. Open your seam.
8. Fell the fold over.