Draw a line around the neck band and bottom hem of the shirt, both a 1/2 inch in, then cut along the lines. Draw a straight line from the bottom of one armhole to the opposite shoulder and CUT. Pin detached hem to the top of the shirt so that it fits the new opening.
STEP 2: SHIRRED THING
Once the hem fits, trim excess, unpin it, and sew it closed. Mark the middle of the front and back of the shirt, then mark 3.5 inches on either side of the center. Sew a running stitch within those 7 inches, 1/4 inch from the cut edge, and PULL THREAD TO CREATE SHIRRING
STEP 3: STRING SECTION
Place the detached hem back on the opening and sew it on 1/4 inch in from cut edge. Cut the discarded sleeve so it lies flat. PLACE THE BOTTLE CAP IN THE CENTER OF THE SLEEVE, cut the ends into strips, knot the ends around the cap, and tug on the edges to curl them.
STEP 4: CAP IT OFF
Snip open the detached neck band, then sew the ends to the sleeveless side of the tee as a strap, adjusting it for length. Pull and stretch the cut edge of the strap for a curled effect. ATTACH THE COVERED BOTTLE CAP to the front of the shirt with a safety pin.