pop it! No, I don´t really mean to pop it, but to drain it. I use a needle, as clean as possible (put in in desinfectant, and desinfect the skin as well) to prick just a tiny hole, desinfect it and cover it afterwards. I feel that blisters tend to burst uncontrolled (rubbing in shoes or banging it on something by accident), leaving a far bigger hole and greater chance of infection. Whatever you do, don´t touch it with dirty hands or instruments. I agree that the best way is certainly to leave it well alone, but who is lucky enough not having to wear shoes for a week??