Watercolor sketchbooks are really expensive. So, I bought a square of full-grain leather, and a leather sewing awl.
I cut off part of the leather square, and cut it in half, then I sewed each half onto the square.
To get the threads nicely spaced, I used a drafting compass to punch a hole, and then rotated it, punched the next hole – repeat all the way around.
Then, sewing was really easy. I just found a video on YouTube showing how to use a Leather Sewing Awl and I did that (I think it’s a lock stitch.)
Then, I stuck in some watercolor paper, and viola! I have a refillable sketchbook.
When I was done, I used a Dremel to carve my initials into it – just for fun.
I fold it top down, instead of side to side – I don’t know why, I just like it that way.
The whole thing was done in one night, and cost $20 for the full-grain leather, and $10 for the sewing awl.