Punch at one angle
The stitch follows the holes. Get those right.
Two reasons, nearly always: the stitch line wanders and the edges were never finished.
A saddle stitch looks good when the holes were punched at the same angle and the needles went in the same order every time. That's it — the stitch itself is simple.
Edges take longer than people expect and change a piece entirely. Bevel, sand, burnish, repeat, and suddenly the work looks like something from a shop.
Both are easy to coach from photographs. A close-up of the front and back of a stitch line shows angle, spacing and tension, and the fix is usually one specific habit.
The stitch follows the holes. Get those right.
It's the difference people can see across a room.
Cheap leather, sharp tools, no pressure.
Twenty minutes, free, on your stitching and what to change first.