All you need is this or this clear iPhone case and a template, but I couldn't find a template online, so I made my own. It fits seamlessly into the Incase Snap Case or the iLuv Sleek Hardshell Case. Just place the art inside of the clear case and there you have it! A new case!
Here is the blank EPS template, for those of you who use Illustrator and want to make your own.
I also made these designs for myself. Feel free to download below. Update, I made sure the designs print on an 8.5 x 11 page! Just remember that these are free for personal use, but cannot be used for commercial purposes.
If you guys are looking for more printable templates, please see my other post.