Until around 1916, making soap at home was commonplace. Using wood or plant ashes and leftover animal fats, families produced their own soap for cleaning their clothes and themselves.

During World War I, when animal fats were in limited supply, German scientists developed synthetic detergents — and commercial soap was born. Homemade soap became less of a necessity, and gradually the practice dwindled.

In recent years, back-to-the-landers and simple-living adherents have revived the homemade soap-making process — but it’s not only in favor with those who leave the big city for rural life or those with an anti-commercialist bent. For anyone interested in living as self-sufficiently as possible, it makes good sense to make your own soap.

Homemade soap is good for your wallet: you can make big batches of soap from scratch for less than it costs to buy bar after bar at your local drugstore, and you can reuse leftover bits to make new soap.

It's good for your body: without all the potentially harmful chemicals in commercial soap, homemade soap is of superior quality; people with sensitive skin often find relief when they stop using store-bought soap and start making their own.

And, homemade soap is good for the environment: it lacks the synthetic materials in conventional bar soaps that eventually accumulate in our waterways and put natural resources at risk.

Step-by-step instructions for making soap at home are widely available online and in various DIY books.

If you’re ready to start making soap at home — and reaping its many benefits — read up on the process and follow these five soap-making tips.

1. Make sure you have everything you need at hand before you start.

There’s nothing worse than trying something new and realizing halfway through that you’re missing something — especially when you’re attempting something as involved as making soap.

Aside from the essential ingredients (lye, water or another appropriate liquid, and fat), you’ll want to set up your soap-making station with these must-have tools:

  • Rubber gloves and protective eyewear, such as goggles or glasses
  • Two large mixing bowls made of a material that will not react with lye: strong plastic, stainless steel, glass, enamel. Do not use flimsy plastic, aluminum, tin or wood. One bowl with a lip for pouring will be helpful.
  • Assorted mixing and measuring spoons. You’ll want at least one heat-resistant plastic or stainless steel spoon for stirring the lye/water mixture, as well as another wooden spoon, wire whisk, or rubber spatula for combining the elements. An electric stick blender, while not necessary, will save you time and energy. Measuring spoons will come in handy if you plan to use additives such as essential oils.
  • An accurate scale for measuring liquids.
  • Two accurate candy or meat thermometers for determining the temperature of your liquids.
  • A mold for shaping your soap. The best materials for soap molds are glass, plastic or stainless steel. Wood or cardboard works if you line it first with waxed or greased paper.
  • Rags or paper towels to wipe up spills. Especially if you’re working with lye, you’ll want something within reach to quickly clean up messes.
This list will vary depending on the type of soap you're making (see tips 4 and 5) and whether you're adding elements to your soap like essential oils, fragrances or natural decorative items.

2. Measure every ingredient accurately.

No matter if you’re making soap from scratch or are reusing scraps to make new bars, you will want to follow your recipes strictly.

One inaccurate measurement could result in a foul-smelling, unattractive, or otherwise ruined batch of soap.

Three guarantees against a mishap are an accurate scale (measuring to 1/10th of an ounce, if possible), a lye calculator (many are available online; for one example, see The Summer Bee Meadow Soapmaking Calculator), and two accurate thermometers (to ensure the temperature of the lye/water and of the fats are the same before combining them).

Different oils require different amounts of lye to become soap, so make sure you know their saponification indexes — a measure of how much lye is required to turn that oil into soap —  before starting.

3. Educate yourself about the dangers of lye — or avoid using it.

One of the main ingredients in soap is a caustic substance — sodium hydroxide, or lye.

People have been making soap at home with lye for centuries without incident, but it is a dangerous substance, and handling it requires a lot of care and attention.Lye

Lye, in whatever form — grains, flakes, or pellets — can degrade materials, strip paint, weaken textiles, and, most gravely, burn skin or eyes.

Prevent the latter by wearing long sleeves, rubber gloves, and goggles or glasses (raw soap residue is also potentially dangerous, so take care even when cleaning up).

If lye does get on your skin, apply vinegar immediately to neutralize it; if lye is spilled on a surface, wash it right away with water and detergent.

Even lye fumes can burn, so work in a well-ventilated area. For those who want a simpler, and safer, approach to making soap at home, there are options.

One way to ease into soap making without the worries of using lye is by melting down blocks of soap base and then adding essential oils, fragrances, or colors to it in a process called melt and pour, or soap casting.

4. Try different techniques for making soap at home.

One great thing about making soap at home is that you get to control what goes into it.

You also have a number of options when it comes to how you make your soap. You aren’t limited to the standard process of making soap by adding lye/water to a fat such as tallow, lard, or olive oil — a method known as cold process.

Another, less well-known technique is hot process, in which the lye/water and fat are heated to boiling together and cooked until they are saponified.Try different soap making recipes.

Hot-process soap doesn't take as long to cure as cold-process soap, and it can be made in an oven or crockpot.

Intimidated by the thought of using lye, or just want a simple, enjoyable craft project to do with kids? Try melt and pour soap, which is made exactly as it sounds: by melting down blocks of soap base, adding whatever elements you want, and then pouring it into molds.

Rebatching, or hand milling, soap is yet another option; soap makers often use this process to correct an error in a cold-processed batch of soap, but you can create hand-milled soap with a bar of plain, fragrance-free store-bought soap and a few other ingredients.

You grate the soap, combine it with a liquid, melt it, put in your chosen additives, and then pour it into molds.

It's an easy way to try your hand at soap making — and it lets you turn a boring bar of processed soap into something special.

If you want to go the other way and try more complex, inventive soap techniques, think felted soap, liquid soap, and the classic soap on a rope.

5. Experiment with different recipes — or create your own.

If you're going to make your own soap at home, you should take full advantage of the freedom it affords.

When it comes to making soap from scratch, you can use animal-product oils, like beef tallow, or vegetable-based oils, like sunflower or canola, and liquids other than water, such as milk, tea, and even beer.

Homemade soapsAside from the basic ingredients in soap, opportunities for additives abound: essential oils, such as rosemary, bergamot, and lavender; vegetable-based oils, such as palm oil, coconut oil, and olive oil; fragrance oils, such as vanilla, rose, and peppermint; natural color, from clay, botanicals, oils, spices, or herbs; and even decorative items, such as flower petals.

The best approach is to find a basic recipe for soap that you like and then add to it.

Be sure to research the additives before you use them — some may not be effective in soap, others might spoil once they’re added to soap, and essential oils should be blended with a carrier oil, such as olive oil, to neutralize their irritant properties.

Popular homemade soaps include coconut milk soap, which substitutes coconut milk for water and gives a creamy lather; castile soaps, made of pure olive oil; and lavender soap, enriched by combining other essential oils such as patchouli and orange.

Once you get comfortable making soap at home, you'll inevitably end up with leftover bits of soap or batches that didn't turn out quite as expected. Instead of tossing it, reuse it: rebatch the soap and make gifts for friends, sprinkle shavings in the tub for a luxurious bath, or add bits of leftover soap to new batches to create a colorful speckled effect.

More resources:

Soap Safety Guide (dangers of lye)

Hot Process Soap Making: The New-Fangled Technique

Soap Making Recipes for Easy Homemade Cold and Hot Process Soaps

And for a quick tutorial on starting your soap making quest, check out this video:

Photo credits

Measuring: madaise/Flickr

Lye: Lye on Wikipedia

Trying different techniques: madaise/Flickr

Different recipes: soapylovedeb/Flickr

MNN homepage photo: Floortje/iStockphoto