For a burn, keep an aloe vera plant around. They take almost no care (just a little water every now and again) and multiply easily. As soon as possible after the burn occurs, break off a leaf of the plant and rub the sap juice of the plant over the burn. Apply again for a day after washing or just to keep it moist. This will not only prevent the blistering, but also keeps the skin from drying out and leaving that ugly brown blotch that usually results from a bad burn.