Whatever recipe you choose, or create, make sure that you measure the ingredients
in correct proportions, and add them at the proper times. It is generally best to weigh
the lye and oils using a kitchen scale, instead of measuring them with measuring
spoons or cups, because different materials have different densities, and volume
measurements can be inaccurate. Also, it is important to use a lye calculator to
determine the amount of lye needed for your recipe. Using the calculator, you can
adjust the amount of lye you want to use based on the amount of fat you want
leftover in your soap. The lye will only saponify a certain amount of oil, so to have
more oils leftover, use less lye, or vice versa. Soap with an excess fat level above 5%
will moisturize skin better, and make it feel softer, than one with less than 5%;
however, some people might feel that the soap with 5% or more excess fat level leaves
their skin feeling greasy. An important consideration when calculating the amount of
lye to use is, of course, skin type; when making soap for dry skin, you would want the
excess fat level to be closer to 5%, but if the soap is being made for individuals with
greasy skin, less than 5% will produce a cleaner feeling.
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