What makes a shampoo a shampoo? They’re foamy, lathery, bubbly products intended to clean your hair and scalp by removing dirt, oil, pollution, sweat, skin cells and styling products. As our hair is acidic – virgin hair can have a pH as low as 3.7, while damaged hair becomes more neutral and closer to 7, the pH of water – we need our hair products to have an acidic pH. As our hair and skin are negatively charged or anionic, we generally use negatively charged (anionic) ingredients as cleansers.

Handmade soap is lovely for our skin, but as it has a pH of well above 8, it can prevent the cuticle from lying flat, leading to friction, tangles and damage as well as a reduction in shine.

The main ingredient in any shampoo are the surfactants, which clean by acting like little emulsifiers. They have a hydrophilic or water loving head and a lipophilic or oil loving tail, so when they encounter something gross, they grab on with the oily end to be rinsed away easily with water. (The use of synthetic detergents is why you may see shampoo bars listed as syndet bars.)

We can create so many different shampoos by making small alterations here and there.

A conditioning shampoo contains a positively charged (cationic) ingredient that can increase shine and reduce tangles, like Honeyquat. These shampoos can range from lightly conditioning to complete 2-in-1s depending on the formulation and positively charged ingredient. They are suitable for all hair types, and may contain emollients.

A moisturizing shampoo contains emollients, like glycol distearate or water soluble oils, butters, or esters, and many will have a creamy, pearly appearance that tells us it’s more moisturizing. Great for normal to dry hair, they may contain conditioners.

A clarifying shampoo is one that contains no moisturizers or conditioners. Its purpose is to remove all those icky things, so it’s a more intense cleanser. Great for all hair types, especially oily and very oily.

A baby or “no more tears” shampoo has a neutral pH with low surfactant levels, while a medicated shampoo might help with dandruff.

As an aside, a dry shampoo isn’t a shampoo at all, but it’s great for absorbing oil to make your hair and scalp look cleaner. You can find liquid versions, which generally contain alcohol as a solvent that makes it spray-able, and dry ones that don’t. I make my dry shampoo by combining 67% baking soda and 25% arrowroot powder with 5% Crafters Choice™ Slick Fix - Oil Locking Powder to increase oil absorption. I package it all up in a powder shaker bottle with 3% dried peppermint leaves or lavender flowers to impart a fresh smell.

In any shampoo, we want to include ingredients like hydrolyzed proteins or amino acids to form a very light, hydrating film on the hair strand, humectants like glycerin or sodium lactate to draw water from the atmosphere to hydrate, essential or fragrance oils, and preservatives to keep the product safe from contamination. Almost every liquid shampoo has some kind of thickener – everything from salt to Crafters’ Choice Bubble Wash Thickener to xanthan gum – making it easier to pour and use.

Why choose a solid shampoo over liquid? Thickening liquid products isn’t as easy as it sounds. Using anything with vanilla can thin them out, while adding citrus can thicken too much, or they may have no effect at all. Tried and true formulas are suddenly too thin or gelatin thick. Sure, that’s actually pretty fun, but not so great if you’re trying to squeeze it from a bottle.

Solid bars can easily contain conditioners like Crafter's’ Choice Emulsifying Wax conditioning or conditioning plus, or any emollient from shea butter to coconut oil to argan oil. In liquid products, we’re confined to cationic polymers, like Honeyquat, and water-soluble emollients to avoid separation and fails.

The base of my shampoo bar is always my favorite, sodium cocoyl isethionate (SCI), a gentle cleanser with an elegant skin feel that offers very creamy, dense bubbles and lather. I combine this with Crafter's Choice™ Lathanol LAL Coarse (SLSa), a powdered surfactant that offers big bubbles and lather, and a liquid surfactant, generally Crafter's Choice™ Bubble Up as this increases the mildness of the cleanser and helps the solids melt easier in the double boiler. This blend generally works for all hair and skin types. Once you get the base you want, start playing around with small batches by adding 5% of this and 3% of that until you create something uniquely yours.

This humble little shampoo bar started my quest to learn everything I could about chemistry, to understand why one combination worked for me while another was better for my best friend, and to understand how I could tweak it for different hair types, which led to creating my blog, writing e-books, becoming an instructor, and writing this column. I’m not saying a shampoo bar can change your life, but you never know!