My english is so bad, so i will use very few words.
Step 1: Materials
Step 2: The pattern
You can use Photoshop, Gimp, MS Paint or download my version. (3 images in a .ZIP)
Anyway, be sure that yu don't make diferent sizes.
Step 3: Printing
Step 7: The final result.
i hope you enjoyed it.
if there is any cuestion, i'm here ;) xD