What's a good way to cure coldsores forever?

No cure: Although there is no cure for canker sores and they often recur, you may be able to reduce their frequency by: 1. Avoiding foods that irritate your mouth, including citrus fruits and acidic vegetables and spicy foods 2. Avoiding irritation from gum chewing 3. Brushing with a soft-bristled brush after meals and flossing daily, which will keep your mouth free of foods that might trigger a sore.