Can you tell me what can i do when my blister pops?

Clean and cover.: Clean the open area with mild dilute soap and water. Apply a thin layer of bacitractin (neosporin more prone to cause contact dermatitis) and cover with a bandaid to protect it and aid healing. Don't wear clothes/shoes or use tools that causes the blister in the first place without padding or if it hurts to do so. Watch for infection and see a doc if increased pain, pus, redness, fever, etc.