If your machine has a zig zag, it probably has the blind stitch too, check it out. Very similar to the blanket stitch but has the same results. Just try it first on something else so you have the stitches all going in the same direction. If you use matching thread in each section, the stitching will barely be visable. Try different lengths and widths; alot depends on the size of each section of color and where you place the stitching.
I like the idea for the ball.
Carol J.