The buttons are just for decoration. You could design a clasp or button-closure for this, but I prefer to have mine not, as I like the flexibility in size I have when I don't have to clasp it. I often carry different books along with my Bible.
The inside is just a fat quarter I bought that has complimenting colors. The outside is made up of strips from a Moda honey bun (Soiree). The buns come with many strips, so as I said, I will be making a few more of these, with different patterns of strips. I bought my honey bun off eBay, as it was less expensive than other sources. This was a fun and easy project, and fairly inexpensive if you use the honey bun for multiple projects.