Slip on safety goggles and latex gloves to protect those beautiful eyes and hands. Also don a comfy shirt with long sleeves when making soap to protect your skin from any splashes.
Pour 6 oz. of water into a glass measuring cup. Add 2.25 oz. of lye to the water, and stir slowly using a whisk until the lye is dissolved. You may feel like you're conducting a science experiment, because when lye comes in contact with water, it heats it up and emits fumes. Try not to breathe them in. Set the cup aside to cool in a well-ventilated area.
Pour 10 oz. of olive oil, 6 oz. of coconut oil and 1 tbsp. of castor oil into an empty glass measuring cup. Melt the oils in the microwave in 30-second increments. Take the temperature of the oil with a candy thermometer. The oil mixture should be between 90 and 110 degrees Fahrenheit before you proceed to the next step.
Pour the warm oils into the water and lye mixture. Whisk slowly until the mixture resembles the consistency of pudding. Are you starting to feel like a domestic goddess yet?
Pour the mixture into a loaf pan lined with wax paper. Cover and let it cool for at least two days. It will resemble a block of white chocolate fudge, but don't let anyone sneak a few bites.
Put on gloves and goggles and tap the soap block out of the loaf pan. Cut it into bars; they can be as big or small, as thick or thin as you like. This recipe should yield 4.5 lbs. of soap.
Let the soap bars sit (or "cure") for at least three to four weeks before using. The soap is still processing, and it needs to absorb the lye before it will be mild enough to use on skin. Store unused bars in an airtight container for up to six months. In addition to putting them into heavy rotation into your own beauty routine, these bars make thoughtful hostess gifts. Everyone will ooh and ahh over what a sassy, crafty lady you are when you tie a ribbon around one of these.
Do a skin test before using the soap all over your body. Swipe the finished soap bar onto your wrist in a small patch, and wait for at least two days. If you have no reaction, use the soap in the shower. If there is redness, itchiness or irritation where you slicked on the soap, don't use it.
Lye is a toxic substance that will burn skin and irritate your eyes, nose and mouth. As the soap sets, the lye interacts with the oils to form soap and glycerin. There is no lye left in the soap after the saponification process. Always wear latex gloves and safety goggles when making homemade soap, and avoid breathing in fumes. Work in a well-ventilated area. Allow the soap to sit for the indicated amount of time to avoid health risks.