How to: Custom Borders for OUYA/Android?

Hey guys… so I have retro arch for OUYA and I love it so far. Ive used the borders for 4.3 display Roms so far that came with the app, but I have seen people make their own. I dont know Where to start with this. . I really want to make my own. Can someone give a basic step by step on how to create your own borders, what file type, program to use to edit if needed, where to place them, etc… ??

I appoligize if this had already been answered somewhere else, I just have not been able to find it.

Thanks!

Here you go: http://filthypants.blogspot.com/2013/10 … rders.html

Awesome. Thanks!