All you need is a clear case, scrapbook paper, and a exact knife (or something that can cut small areas)
I saw this on pintrest and it led me to "mags rags to riches" blog.
I have tried this and it is pretty cool being able to change the look of my case at a cheap price single pieces of scrapbook paper at Michael's are reasonable around $.50 to $1.00
Try it out its fun. I had to return my clear case though because it was peeling off my zagg invisible shield.
**Disclaimer this photo is not mine**