There are a few things that you can do in order to help decrease the melanin in your skin. One of the best things that you can do is to avoid excessive sun exposure. If you must be in the sun, be sure to wear sunscreen and cover up as much as possible.
You can also try using skin lightening products that contain hydroquinone. These products can help to lighten the skin and make the melanin less visible. Finally, you can consult with a dermatologist to see if there are any other options available to you.