Put any color polymer clay into any flexible mold you have (in this case I'm using a tiki ice cube mold from a local dollar store).
Freeze the polymer clay (in the mold) for about 10 minutes. This helps the clay keep its form when you pop it out of the mold.
Pop your charm out, stick your eyepin in it, bake it (according to instructions on the package), and then paint it (if you'd like) with nail polish or paint. I used a multi-pack of metallic nail polish I got from a local beauty store for a very low price. ($3 I think).
Open your jump ring and attach the charm to the necklace. Ta-da! You might want to put a little super glue on the eyepin where it enters the clay for some extra durability. Your necklace is now perfect to wear out to Mardi Gras, a cookout, or with any other outfit you find appropriate.