In case you didn't know: Your body produces an oily substance called sebum, (which sounds gross but isn't) and protects your skin by forming a thin barrier preserving moisture, promoting elasticity. But, since nature is imperfect, many of us produce too much or too little sebum.
Our natural moisture is striped by climate, soap, hard water, or any manner of things.
We are left having to replenish not only our moisture, but a barrier to keep it from evaporating or washing away.
So there are two parts to staying moisturized- moisture, and oil to keep it in place. A lot of people (particularly those who live in moist climates and don’t tend to have dry skin) are able to simply “lock in” the moisture they already have with an oil, like my personal favorite, cocoa butter. (I use the steam deodorized when I want to smell like something other than dessert).
Many people use cocoa butter as a base for solid lotion bars and lip balms, since it is a fat that's solid at room temperature and melts at human body temperature. (Fun fact: that's why chocolate melts in your mouth!)
Cocoa butter can also easily be melted with other oils, including essential oils for scent, to make a solid, semi-solid or totally liquid moisturizing oil.
Getting the texture you want simply depends on your proportions and mixing techniques.
A lot of people get the consistency they want using hand mixers to ensure a uniform blend before the cocoa butter returns to room temperature and regains some measure of solidity.
One of the most effective times to apply it is straight out of the bath, when your skin has been saturated with water. Some people even mist themselves with water from a spray bottle and then apply an oil barrier to keep it in (I love using rosewater, then coating with deodorized cocoa butter).
Contrary to popular belief, the “oily” residue from barrier oils should absorb quickly if you use sparingly. If they don’t, it’s probably because you’ve either used too much, or you don’t have enough moisture in your skin in the first place, and simply layering oil on dry skin does nothing for its health or looks.
For example, I used to live in a place with extremely hard water, meaning there were incredibly small mineral particles in my bathwater. After I dried off from a shower, it felt like I was covered in powder. The minerals would work much the way a shine-control facial powder would- they’d absorb the moisture. As a result, barrier oils did nothing for my dry skin, and simply felt oily.
This is when an emulsion becomes necessary. An emulsion is a mixture of oil and water, and it’s what most people think of when they think of lotion. This way, there’s only one step, and you don’t have to worry about having moisture already on your skin before applying a barrier. You might proclaim:
“But oil and water don’t mix!”
You’re half right. Oil and water don’t mix on their own- they require an emulsifier- an agent that bonds oil and water. There are lots of different emulsifiers, but if you’re looking to keep it natural, stick to lecithins. Lecithins are used in food and beauty produce to bond oil and water, and are simply extracted portions of plants with a fatty element- soy and sunflower seed lecithin are the most common, and the best soy lecithin is entirely mechanically extracted (some are extracted using chemical solvents.)
The process is just as simple as barrier oils- low heat and mix. You just blend in an emulsifier. Without all the chemical preservatives, your lotion has a shorter shelf-life than most store-bought lotions. Which is good, since most of those preservatives are not good for your health and are very drying to your skin.
Many lotion makers either stick to small batches they intend to use quickly, or prolong their shelf-life with natural preservatives. The proportions are usually about 1 part emulsifier, 3 parts butter or oil, and 6 parts water, but you can experiment until get a texture you like.
So there you have it, you know how to make moisturizers! Go experiment and make your own.