To prevent the chunks from sticking to the cookie sheet, apply a thin film of non-stick cooking spray such as Pam, or a silicone spray lubricant. Either one will work. Wipe out the excess with a paper towel and leave only a very thin film.

A seasoned cookie sheet will not require anything to aid the release. Also, if you added fragrance oil to the wax, it will act as a release agent. Therefore you will not need any spray.