I have a detailed instruction leaflet on making a T-shirt which takes you through making a pattern, making up, including how to stabilise seams. It explains how to knit the band, shape it with steam and attach it achieving a very neat finish. A 2.5mm twin needle is used to make the seams, and a 4mm twin needle is used to topstitch the neckband and turn up the hem. Although a straight stitch is used, using the twin needle allows the seams to stretch.