To make soap, measure the lye, water and oils according to weight. Pour the water into a glass bowl, and pour the lye into the water. Stir the lye and water combination with a non-reactive spoon. Melt the desired oils in a saucepan, and allow them to cool to 95 to 115 degrees Fahrenheit. Slowly add the lye mixture to the oil, and stir the mixture to trace. Pour the soap into molds to harden.
Use a recipe to determine how much of each ingredient to use. Handle lye with caution, and wear safety goggles and gloves when making soap. Always pour the lye into the water rather than pouring the water into the lye to prevent potentially dangerous reactions.
Before washing soap-making equipment, rinse the equipment with vinegar to neutralize the lye. When the lye mixture cools to the same temperature as the oil, pour the lye mixture into the oils, and stir for at least five minutes or until the mixture thickens to a pudding-like consistency.
If desired, stir in essential oils, color additives or other additions immediately before pouring the soap into molds. After pouring the soap into molds, allow it to remain undisturbed for 24 for 48 hours. Unmold the soap, and cut it into bars. Allow the bars to cure for four to six weeks before use.