I have seen this on Pinterest multiple times and FINALLY had a chance to give it a try. I thought it would be perfect for Christmas.
I found that hardcover books work best as the covers are strong enough to adhere to the wall. I tried a couple paper back and torn books and the back page would stay stuck to the wall and the rest of the book would tear off.
Hardcover Books (different sizes with varying page patina)
Vintage Post Office Box
Staple chunks of pages starting at the back. Make sure staple goes through all pages on each side except one. You will glue that page down to cover the last staple.
Once the page you glued down is dry, repeat this process on the other side.
I used command strips to hang the books on the wall. I alternated different sizes and patina. I also used some single pages to fill small spaces.
I added some Christmas accessories and WAHLA!