Backside is a little rough because the layers are so thick. I use different tools and techniques for different things. Usually I use a stitching groover, make a groove and then use a Tandy diamond chisel, punch all the way through and stitch with Tandy poly braided cord.
But on this one I wanted more SPI and a finer thread. I used a screw creaser to make a line, marked my stitches with my Vergez 7 tpi pricking iron, punched it pretty hard to get it in deep. The used an awl and stitched with Crawford 3 cord linen thread from Royalwood. I think my awl needs sharpening because pushing it through all those layers was tough.