I put the little copper electrode hooks around my ears, one over each lobe. Is that a safe area to put them? Sometimes it stings a bit if there is too much water, but I just assume that means it's working and doing its thing. Also, how far does the signal go in the body? Example, If I do one hand, does the signal reach the other hand, or opposit leg, etc? Or should I zap each arm etc, daily for better distribution?