Hi Debbie, I've seen it used along with Citri-Strip which is a paint remover product. You apply the remover liberally, then add a layer of plastic wrap so the remover doesn't dry out so quickly. Wrap can also be used along with tape to mask off certain areas you don't want to paint. Also, even as you're painting if you want a mottled finish of 2 or more colors you can use plastic wrap to create various designs in the paints.
I have posted some videos for you that give some good suggestions/ideas. Good luck on your project!
I'm wondering if you're thinking about a technique for using Unicorn Spit. Often people put the product on in various colors and patterns then add a plastic wrap top so they can smush everything around to get the final design. Here's a project that uses a variation of that technique from another Hometalk member. I hope this helps you. Wishing you the best.