Using a sterilized needle or razor blade to make a small hole is the ideal way to burst a blister while minimizing the risk of infection, according to WebMD. Applying a flame to the needle or razor blade sterilizes the tool, as does an alcohol rinse.
In addition to sterilizing the tool, it is important to wash hands and the blistered area thoroughly, states WebMD. After making a small incision, slowly drain the clear fluid from the blister. Yellow or white fluid may indicate an infection, which warrants medical attention. WebMD advises against bursting blisters unless the blister is large, excessively irritating or painful.