Don't pop it! It has a chance that it could get infected. If that happens, go see a doctor. Don't touch the blister! Just leave it alone and rest a lot until it heals. Also, whatever caused the blister, do not do it again until healed.
savlon, some cream basicallyor'eughh' you could pop it,popping hurts and its disguisting but it goes away quicker,the safest way is to put cream on it and place a plaster on top,hope this helps :)
Blisters form because your body is trying to prevent any further damage to skin and to heal the damage that has already been done from rubbing etc. This is why the disgusting pus is produced to help...