If you are feeling a little more adventurous, go for a 9-patch. You could do it in two colours if you want, or use three--one colour for the four outside squares, one colour for the 4 inside squares and one colour for the center square. (Then if you really feel adventurous, you can cut it apart and put it back together again for a Disappearing 9 patch which looks lots lots harder than it is.)
Lots of easy patterns out there. You just have to take the plunge.