Sav-On drugstore oil. You can also use this oil on a washcloth in the shower. If you put oil into the tub, you have spend extra time cleaning the tub. Not a frugal use of your time. The washcloth idea works just as well, without the extra cleaning.
Some people like to use it after a shower, while they are still damp.
He recommended that people who shower more than once per day, to use soap only one of those times. He suggested that drier areas of skin, such as on the legs, only be soaped every few showers, especially if you already have a problem. Course, you still have to soap your hands all through the day, to cut down on germs. I see hospitals use it, but they could just be getting a discount. Drink lots of water because it's important to hydrate from within.