The yarn I used came in short lengths and I had to tie it in the back and start again from where I left off. If I made these flip flops again, I would definitely use one length of yarn.
*If you don't know "Death Note," you should.*
I used black card stock with white paper and I sewed the pages together with black string. Inside I attached a printed copy of the rules. The "Death Note" title is actually painted on. I'm not good enough to do it by hand, so I found a Ryuk handwriting font, printed the words, and cut them out to make a stencil.