Grounding; Connect with the earth (literally)

Just because it's simple and doesn't cost a thing doesn't mean it isn't hugely beneficial.
Our body needs the negative charge of energy from the earth's electrical charges; connecting our "conductor"- any part of our body- with the earth's surface (i.e. simply walking barefoot outside!) has been shown to reduce oxidative stress, inflammation, and pain.

Check this out:
As the Journal of Environmental and Public Health states:
”It is an established, though not widely appreciated fact, that the Earth’s surface possesses a limitless and continuously renewed supply of free or mobile electrons. The Earth’s negative charges can create a stable internal bioelectrical environment for the normal functioning of all body systems which may be important for setting the biological clock, regulating circadian rhythms and balancing cortisol levels.”

Read more from Dr. Josh Axe about grounding or "earthing"