Place the end of the ribbon next to the collar on the top of the shirt (upper shoulder). Pull the measuring tape to the bottom of the shirt.
Place the end of the tape at the seam under the sleeve and pull the tape measure through the shirt until the seam under the opposite sleeve.
C Sleeve Length
Place the end of the ribbon in the center of the back of the collar and pull the measuring tape along the top seam of the sleeve. When you reach the shoulder, hold the tape in place and continue to pull the sleeve down until you reach the sleeve hem.