DIY: Watercolor Sketchbook (No Bookpress)

Here's an easy bookbinding tutorial! There's a lot of reasons why I wanted to make a watercolor sketchbook

1. There aren't great watercolor sketchbooks out on the market right now that have artist grade 100% cotton paper. Pentallic used to make a great watercolor sketchbook but they discontinued making them (**EDIT: Amazon has the Pentallic sketchbook now! I bought it and it's pretty good!) . Arches has a good sketchbook but it's pretty pricey for the amount of paper inside.
2. I could customize what size I wanted
3. I could choose my favorite watercolor paper!
4. Watercolor paper is trickier to bind because of how heavy-duty it is. So I thought I'd share a method to an easy way to securely bind paper together.