My technique is to ensure my edges are STRAIGHT. I use a stationary belt sander to ensure the edges are straight and square.
I use a sewing machine 99% of the time, but whether you are using an awl or thong chisel, I think it would help you to make a couple passes with a stitch grover. This will help you keep a little more straight and allow for a "sweet spot" for your stitch holes. As I said, this is my technique. I'm sure there are many more.