Start off with a clear glass bauble and a bottle of polish that you don't mind using alot of. I used China Glaze holographic "Infra Red". I usually would balk at using an expensive bottle, but I accidentally got 2 of these when they went on clearance. That and I really wanted to see if the holo would translate to the ornament.
A neat trick I found was to pull up on the wire bit on the cap. It will come up but then stop where there is a little bend in the wires. This keeps it from pulling all the way out and you can lift the cap off easy. If the wires pop out all the way don't fret. You can thread them back into the holes in the cap.
Pour your polish into the ornament. Don't be stingy. I usually pour nearly the whole bottle into it. You will swirl the polish inside to coat the whole ornament. If you are working with a older polish, maybe thin it with polish thinner before pouring it into the glass to make it easier to swirl. Then pour the polish back into the bottle. Polish is thick so you might be holding the bauble over the bottle for a while and it drips slowly back in.
When you get tired of holding it and you think most has dripped out turn it upside down and let it dry. You can try to balance it on a paper towel, but I live with cats and that was a mess waiting to happen. So I found this plastic container at work. I have no idea what was packed into it, but it was being thrown away so I grabbed it. I think you could use maybe an egg carton or ice cube tray to prop up the ornament while it dries. Something that can keep the drips from making a mess. You could use the packaging the ornaments came in, but I like to use them to store the finished ornament in. I left them overnight to dry.
In the morning you will see a puddle formed under the ornament.
Put the cap back on the ornament and you are done! You can see the holo effect in this photo. I love it!!
I had so much fun making these that I gave them all to my coworkers for Christmas. It was a hit!