The case is cut to a template but fitted to a pipe. The maker keeps a stem to hand and shapes the pocket around it, because a case cut only to a pattern will either grip a fatter stem or let a slim one slide.
It is stitched by hand with waxed thread rather than run through a machine. Two needles work the same line of holes from opposite sides, so if the thread is cut anywhere along the seam the stitching either side of the break holds instead of unravelling. It is slower and it is the reason these last.
Edges are bevelled and burnished down until they are smooth and sealed, which is what stops the leather fraying along the cut line. The press stud is set last. Grain and colour move between hides, so a batch will not be uniform.