Use a cutting blade on a rotary tool to cut off the tops of the doll heads. Then remove the head from the body.
If you wish, remove your eyes. If you're using vintage porcelain doll heads, most of them already have holes where the hair and eyes will be attached, so cutting them won't be necessary.
Place a small amount of soil inside the doll's head and fill it in with the plant. Add moss around the edges.
Use cups, vases, and other containers to display doll heads.
