Now we begin the fusion of T-shirt to sweatshirt in true sci-fi style (not really). Beginning at the shoulders, tuck under about ¼” of the t-shirt raw edge under and stitch to the sweatshirt. From the shoulders, stitch the neckline, armholes, and side seams, making sure to only sew through the front layer of the sweatshirt.
Sew on the waistband ribbing to the newly cropped top. Make sure you stitch through both layers and work in small stiches close together for the best results.