Step 5: Prepare the Ingredients
Now it's time to take that luke warm liquid bacon fat and measure out the correct amount - I started with about a liter of bacon fat so my 4 cup recipe used just about everything I had. The temperature of the fat was right around 105-110 degrees Fahrenheit - warm enough to keep it liquid, but not too hot for soap making. Cool or heat the fat in the fridge or on the stove as necessary to get your fat to a similar temperature.
To prepare the lye you need to dissolve it into water. My recipe called for 4.2 ounces of lye dissolved into 2 cups of water. I used cold water because I have read that it is better than room temperature water because there is less chance of fizzing up. Fizzing is bad since the lye can burn you if it touches you. With rubber gloves and proper eye protection I carefully measured out 4.2 ounces of lye into a glass jar and then slowly mixed it into my cold water. I continued to stir until the lye was completely mixed in. It didn't fizz at me at all during this process and I felt quite safe.
The amount of lye you use can be adjusted to the particular soap you are making. If you're adding in other oils to the soap, or mixing fats, or superfatting to your own amount, then you will want to adjust the amount of lye you use. Refer back to the fat to lye ratio table link in step 3 to come up with your own recipe.
I readied my bacon bits and my color at this point because once you combine the lye and the lard things start to happen and there is no going back.