The bottle caps I had were large, about an inch across, and 1/2 inch deep, so I cut it down to about 1/4 inch high using old scissors, then sanded the cut edge. An adult should definitely do the cutting! Stuff the cap with cotton balls, until they make a nice puffy seat. Cut a large circle of fabric (printed cottons hide glue spots pretty well), and cut rays from the outer edge inwards towards the center. Put glue around the plastic sides of the bottle cap, and then cover the cap with your fabric circle. Don't worry if glue shows around the sides, you will cover that with trim. Secure the fabric with an elastic band, and let it dry. When it is dry, trim away excess fabric, remove the rubber band, and add trim. I'm fond of embroidered ribbon or crocheted lace for this part, but any heavier weight wide trim will work.
I Want To Be Alone!
8 hours ago