If you have a pustules, which often very painful to touch and visible pus (often yellowish and raised). Then you can use this rememdy to collect the pustules and extract it. But one thing to remember, the pustules has to be fairly aged, meaning it harden a bit and not all watery feeling. Cuz if you try this too early, it'd pop water part only and not extract it fully. Especially careful if you're going to try this on your face. If you don't wait for the right time, it can leave scar!
Finely crush rose mallow leaves - you'll soon notice that it'll turn sticky, then add the salt, not too much, you want it to stick and stay together when you apply it. Then cover the acne area. Wait until for it fully dry, it takes hours. BE PATIENT. Dont touch it. When it has COMPLETELY dry, take it off. Pop the collected pustules if needed.source:
http://www.myacneremedies.com/remedies/rose-mallow-aka-hibiscus-and-salt-pustules
