These balls I made from painted cheesecloth (years ago! - I like to recycle). I made a template from cardboard and outlined it on the fabric. I discovered that the back was more interesting than the front, so I used that.
Some eraser offcuts and a rainbow dye inkpad makes a great border!
Initially I was trying to make a bird stamp, to illustrate a poem, but I wasn't happy with the result. And when I glanced at the offcuts I saw new possibilities.