Combine the baking soda and Epsom salts in a small bowl and until completely combined.
As you stir, add in the rose essential oil.
Repeat the process with the Ylang Ylang essential oil.
Add 1 tablespoon of water and stir well. If the texture seems pasty and will hold form you're ready to move on. If not, add the other ½ tablespoon of water, then stir.
Place a few rose petals into 9 of the mold cavities.
Fill the mold with your mixture and pat it down.
Let them set up for 24-48 hours.
Carefully remove from mold
To store, place in an airtight container in a dry place.