After trimming the arm hole, measure one inch back from the shoulder seam and mark with a pin. Fold the garment at the arm hole with this pin at the top of the fold and place another directly opposite it. Call this point A. Remove the first pin to avoid confusion. For a sleeve for an adult, measure from the shoulder seam five inches on the front and mark with a pin. Call this point B. Measure from the shoulder seam three inches on the back and mark with a pin. Call this point C. With the sleeve right side out place the under seam of the sleeve at A and pin together at this point. The gathers are to come at the top of the sleeve between B and C. For misses and children the measurements should be decreased proportionately. Measure the sleeve on the arm-hole and cut small notches at B and C. Gather the sleeve between these notches one-fourth of an inch from the edge, with a strong thread a little longer than the distance to be gathered. Put in a second gathering one-eighth of an inch from the first. Put in place at points A B and C; draw up the gathering threads to the proper length and fasten by winding around a pin. Arrange the gathers between B and C, pushing them a little closer together in front of the shoulder seam. Hold the inside of the sleeve next to you and, beginning at B, baste first around the plain part, then the gathered part. Stitch inside the basting and bind the seam.
The shirt sleeve is put in before the under-arm seam is stitched up and the sleeve seam is a continuation of the under-arm seam.