First-degree burns can leave a scar, especially without proper treatment. To treat a first-degree burn and prevent scarring, remember these steps: Cool the burn using cool (not cold) water for around 10 minutes or until pain goes away. Apply petroleum jelly to the burn two or three times each day. Keep the burn area covered with a clean, non-stick bandage. If needed, take an over-the-counter pain medication for pain relief and to reduce inflammation. Keep the burn away from direct sunlight. Stay in the shade, wear protective clothing, and apply water-resistant sunscreen that is SPF 30 or higher.