Choose the scent you wish to burn. Remove the lid from the tester jar and set it aside. Place the jar in the microwave for 30 to 45 seconds on high to soften the wax.
Using a butter knife, slide the blade along the edges of the inside of the jar to loosen the wax away from the sides of the jar.
Carefully pry the wax out of the jar using the knife. It may come out in several pieces. Do this over a bowl to catch all of the chunks as they come out.
Remove any previously used wax from your Scentsy warmer. Place the pieces of the tester wax in the top of the warmer.
Plug in the warmer and turn it on.