The first step in making a liquid castile soap is to prepare yourself for the task. Since you will be dealing with a number of chemicals (mild and harsh), wear a long sleeved shirt or a coverall, safety goggles and thick rubber gloves.
Measure 1 ounces (417 ml) coconut oil, 14.1 ounces (417 ml) of liquid soybean oil and 18.8 ounces (555 ml) of olive oil and pour all of them into a crock pot before setting it on high heat for four hours (if it has a setting for hours).
Measure 32.9 ounces of distilled water and add it to a large container. Make sure your container is heat-proof.
Measure 39 ounces of potassium hydroxide, commonly known as lye, and add it slowly to the distilled water. Stir water thoroughly with a glass stirrer until potassium hydroxide has completely dissolved.
Slowly and gradually pour this alkaline mixture into the crock pot containing oils, while stirring it constantly.
Thoroughly blend this concoction for 12 to 15 minutes with the help of a stick blender. You will notice that the mixture will start becoming thick and consistent.
Remove the blender once the mixture becomes too thick for it, and stir the mixture with a spoon. Keep stirring the concoction until it becomes too thick and you can no longer move the spoon in it.
Cover the crock pot and turn it on again for another six hours, this time setting the heat to medium. Heating will reduce the consistency of the mixture. Keep stirring the mixture after every 2o to 30 minutes.
Turn the crock pot off once the mixture becomes clear. At this stage it should have consistency equal to that of honey.
Take a large stainless steel bowl and shift the mixture in it.
Add 80 ounces of distilled water to this mixture and stir well before allowing it to sit for 12 hours or until the thick mixture dissolves completely.
Your homemade castile soap is ready now. Store it in empty distilled water jugs and allow it to age for at least four weeks before you use it.