Earthing is bunk.
I do highly recommend proper grounding for all electrical appliances. Low powered appliances are grounded through the neutral line, high powered appliances have an additional grounding plug. A simple outlet tester should tell you if your house wiring is behaving correctly. Stray voltage is no joke.
Another possible source of stray voltage is static. This is almost impossible to avoid in indoor heated environments. Even the best "earthing" shoes will do nothing because most indoor flooring is an insulative material. The stray voltage you pick up with static is way less than stray voltage you can get from bad wiring and isn't a huge concern unless you're playing with a Van de Graaff generator.
Even if you were worried about proper "grounding" the earth isn't all that conductive, proper electrical grounding requires rods be sunk into the ground. Electrical fences generally use three six foot rods for proper grounding. Home systems are grounded with one eight foot rod. Just touching the earth is not likely to do the trick.
That isn't to say that you won't experience an improvement in health if you try earthing. Barefoot and minimalist shoes may help some people with gait issues through reducing constriction of the foot and leveraging the nerves in the foot that are muted through cushioned shoes to improve gait with biofeedback. Sleeping on a hard surface with no pillow may have postural benefits for relieving back tension and even sinus issues. Spending time outside increases your exercise level, sun exposure and Vitamin D production. Soil also contains beneficial bacteria that you can alternatively pick up through gardening. If earthing got you there and it's helped you, good for you, but it's probably not the actual earth contact doing the trick.
So if earthing helps you, but you're miserable in winter, get some good wool socks (insulative) and thin leather moccasins (water resistant), build yourself a platform bed with minimalist padding, take some Vitamin D supplements, get some exercise, bring in some plants potted in local soil, and enjoy being warm in winter.
(Amusingly this hits just about all of my non-diet blog labels. Even endocrine, since Vitamin D is as much a hormone as a vitamin. Earthing does touch on a lot of real benefits even though the reasoning is all wrong.)