What I did is went to Walmart and got this bag of cheap tennis balls... something like 6.97 for the bag of 12. They are Wilson balls, but not the best quality.
I then used a razor/Utility Knife to cut them... pole the point of the knife in, and your good to go... just cut away from your self... not hard to cut at all...
Here is what I did too with a stencil and airbrush!
