Cut your melt-and-pour soap with a sharp knife into 1/2″ cubes and place 2 cups of soap in a pourable microwave safe container. Heat for 30 seconds at a time, stirring at the end of each interval. Once the soap is completely smooth and melted, allow the soap to cool a bit until it reaches 145° (use the soap thermometer to track the temperature).
Once the soap has cooled, add the desired amount of essential oil and stir until combined.
Use the dye droppers to drop dots of dye onto your empty soap molds, spreading out the colors if using more than one.
Pour the soap into the molds. Stop pouring when the mold is halfway full and spray some alcohol on the soap to spread the color. Repeat with another spray of alcohol once the mold is full and use your popsicle stick to move the color around the mold.
Keep swirling until you like the pattern you have, and then let your soap harden. Once it’s set, pop the soap out of the mold, and you’re done!