Sunburn comes when the body cannot produce enough melanin to prevent UV damage under the sun. Symptoms of sunburn may include itchiness, swelling, and stinging pain. These symptoms may not occur right away; it can take up to 5 hours for them to appear.

To heal sunburn with natural materials you can find at home, I recommend 3 top ways.
Apple Cider Vinegar
The astringent properties in apple cider vinegar can help sooth sunburn pain and stimulate the healing process. The acetic acid contained in the vinegar can also help relieve itching and inflammation.

How to use: You can 1) soak some paper towels into the mixture of apple cider vinegar and cool water and place the towels with diluted vinegar on the affected area until they dry out, or 2) add a cup of apple cider vinegar into your warm bathwater and soak in the water for 30 minutes. Both methods can be repeated when needed.
Note: Don’t use apple cider vinegar if you have abrasions on the skin.

Aloe Vera
The anti-inflammatory and soothing properties in aloe vera can help relieve the symptoms of sunburn.

How to use: extract the gel from the leaf and place the gel in the fridge for about 30 minutes. Place the cool gel on your affected area until it is absorbed by your skin. Repeat this remedy 5 – 6 times daily for a few days.
Note: If you do not have aloe vera at home, use commercial products containing aloe vera gel.

Oatmeal
The properties in oatmeal can help reduce irritation and retain the natural moisture of the skin.

How to use: Cook oatmeal with water to get a runny consistency. When it cools down, apply it to the sunburnt skin for 30 minutes before rinsing it off with cool water. Repeat 2 – 3 times daily as needed.
Note: When applying, avoid rubbing the oatmeal on the skin.