found the video! - https://youtu.be/U4p7hmOnTF0 -
in short summary , the steps are:
1. stixk a Cotten ball into a scrap of nylon pantyhose and snug it up tight into a ball shape.
2. Stick it on a toothpick
3. Tie tightly with thread to hold the ball shape and trim excess sticking out of the way.
4. Apply clay - liquid do in thin coats , baking between each. Cane use thin slices and grout with liquid clay if needed.
5. After baked and cooled , pull out the cotton and panty hose and toothpick.
i saw another video using purpose made balls that were coated with cooking spray to facilitate extraction.
another tutorial was using some kind of paper form.