I am a runner and hiker and occasionally suffer from foot blisters. Over the years I have experimented with preventatives and treatments.
The best preventative I have found for toe blisters is to apply Vaseline or Albolene between your toes to prevent them from rubbing against each other before pulling your socks on.
The best cure I have found requires a large safety pin (1.5 inches), a cotton ball and off-the-shelf 70% isopropyl alcohol. Soak the cotton ball with the alcohol, clean the safety pin and the blister with it, then puncture the blister on the bottom-most edge. Squeeze the liquid out of the hole by pressing it with the cotton ball starting from the opposite side of the blister. When all the liquid is released, press the cotton ball over the pinhole to squeeze a small amount of alcohol into the blister. You should feel it burn a bit. Leave the blister alone after that and go about your life pain-free. Eventually, you can remove the dead skin over the healed skin beneath it using scissors or clippers.
In a pinch, you can use a high proof alcoholic drink if isopropyl is not available. Be sure to use a larger pin. Too small a hole will make it harder to release the liquid and get the alcohol inside.