Place the baking soda in a small glass bowl.

Very slowly add the water, mixing as you go until the mixture is wet enough to stick together, forming a very thick paste.

Add the essential oils and mix well to incorporate them through the whole mixture.

Place the mixture in your mold, pressing it down and flattening the top.

Allow to air dry overnight or longer, until the melts are hard.

Remove from mold and store in an airtight container.

To use these melts, drop one at the bottom of the shower where it will get slightly wet, but not soaked. The slower the water hits it the longer it will last and the better it will work.