Bring 6 cups of water to a boil in a large pot.  Add the soap nuts. 

Cover pot and reduce heat to low. Simmer for 45 minutes. 

Strain the liquid into a glass jar or other container. 

Add 4 cups of fresh water to the pot again, with the simmered once soap nuts.

Simmer again for about 30 minutes.

Strain and combine with the first batch of liquid soap.

Allow to cool.  Once cool, add optional oils as desired.  Store as liquid in the refrigerator or pour into ice cube trays and freeze.