I have really bad and big blisters from running a race yesterday and they are still oozing pus. Should I bandage them or let them air out? They hurt

Blisters. If your blisters are actually draining pus, thick yellow material then you need to see a doctor. If it is a blood blister then you need to make sure to clean them up with soap and water. I would keep them wrapped as they need protection as well as keeping them clean. I would recommend buying "adaptic" dressing as it will keep the gauze from sticking.