Add all the dry ingredients and mix together making sure to break up any lumps.
Add 2 tbsp of water and stir in quickly, note the mixture will fizz up, that is normal. Add in the extra water as required mixing thoroughly, it should hold together when pressed with your hand.
Finally add the drops of essential oil stirring quickly through the damp mixture.
Press the mixture tightly into the trays pressing quite firmly, use a spoon if you need to.
These have to be packed in really tight to prevent them from falling apart.
Leave the moulds for 24 hours to fully dry on the bench, don't be tempted to turn them out before this time as they may end up falling apart.
Place them into a glass jar with a sealed lid to keep the moisture out. Thats it, enjoy.