Time to let your personal style shine.
The challenge is easy enough to understand. You will all be provided with one scan. Using that scan, create a unique wallpaper. Do what you will with it: vector, render, add textures, brushes, text, crop it, stretch it, rotate it, combine images, whatever suits your fancy as long as the scan can be seen somewhere in the wall. Just remember that everyone is using the same image, so you'll want to be creative to stand out. But don't just add some words to it or only change the color and call it your own. Entries like that are guaranteed not to win. Effort is rewarded.
[updated to a larger version]
HERE is the scan.
-Must have your username ON the wallpaper
-Must credit Kohime Ohse ON the wallpaper
-Submit it into "other anime and manga" category
-Failure to comply will result in disqualification
But they're simple enough to follow, right?
Judging will be based on the overall quality and creativity of the wallpaper.