Ugh, dry skin, no fun.
You may want to check out dry body brushing. Along with increasing your fluids.
The lotion I like to use is Nature's Gate Hemp Lotion. I was turned onto this company by someone who was going through chemo. The lotion was wonderful not having so many additives its unreasonable. Also, you can get their lotion without fragrance. I like to add my own when I want to.
You could make your own, but you'd have to keep it in the refrigerator, and find the time to make small batches when you need it.
There is no, I repeat, no such thing as a "natural" preservative. You can add natural antioxidants but they only retard oxidation. It has nothing to do with the bacteria in the lotion itself.
Anytime water or other fluids are introduced to your potion...you are also dealing with bacteria. So sometimes its better to have a lotion with a mild preservative, than one that only uses antioxidants. Black Willow has been used in combination with others for a good result, but be sure you through it away when that date on the bottle of lotion is up.
If you want to skip all that you can either buy a commercial product, or use oils without any water introduced. You can use bath butters. These are easy to make.
Hope this helps.
Wanderingherb