In a large bowl, add 3 cups of baking soda and 1.5 cups of citric acid. To get rid of clumps in the mixture, you can push the powders through a sifter or break them up with your fingers. Citric acid has a tendency to take off nail polish, so wear gloves to protect your manicure. Stir the powders together.

In a separate glass container, add 2 ounces of sweet almond oil, 0.6 ounces of polysorbate 80, and 0.7 ounces of Ginger Patchouli Fragrance Oil. Mix thoroughly.

Add the oil mixture to the baking soda and citric acid. Use your hands to thoroughly mix them together.

Split the mixture in half. Each container will weigh about 22 ounces. To one container, add about 1/4 teaspoon Blue Mica, and to the other add about 1/4 teaspoon Sunset Orange Mica. Use your hands to break up the drops of color and disperse them throughout the mixture.

Begin spritzing each container with witch hazel while mixing with your hands or a spatula. The right texture for molding feels similar to wet sand and holds its shape when squeezed. 

Working in one half of the mold, add some of the orange mixture and then some of the blue mixture. Once this half is full, press the mixture down to compress it and continue layering the colors.

Continue layering into the other half of the mold, compacting it as you go. Finally, add a little extra mixture into each half but don’t press it down. Slightly overfilling with loose powder helps the 2 sides stick together. Clear off any excess powder in the seams of the mold, match up the eyelets, and press together. Apply pressure to the edges of the mold rather than the center to prevent dents. Allow them to harden for 24 hours. When you’re ready to use one, remove it from the mold, place in the tub, and enjoy!