Why should we put magnesium oil on the bottom of our feet? I think my skin is dry and thicker on the bottom of my feet. Would that affect absorption? Would the calves be just as good, or is there a reason you mentioned the bottom of the foot specifically?

Mix the magnesium oil in with a little coconut oil and then put socks on. That should help. If you put it on your calves, it might itch or sting but if it doesn't, that's fine. Or you can do a foot soak in hot water or take a magnesium bath.