@donasmrs-- I don't think it's a good idea to pop and drain blisters. The liquid inside the blister is actually a good thing. It protects the blister from infection, helps healing and serves as a cushion. If you pop it, the risk of infection will be higher.
My advice to you is to buy some of those gel-like blister bandages from the pharmacy and put it over the blister. If you can, wear soft shoes with soft socks to protect the blister. And let the blister heal on its own.
As long as your socks are clean, even if the blister pops on its own, it shouldn't get infected. You can apply some antibiotic ointment on it if that happens.