To naturally remove brown spots from your skin mix some olive oil with some Apple Cider Vinegar.
Apply the Apple Cider Vinegar and Olive Oil mixture to your skins brown spots everyday for 20 minutes each time and after 20 minutes you can remove the olive oil and Apple Cider Vinegar from your skin.
Do this for around a week or two and you should start seeing the brown spots go away and your skin should become much smoother as a result.
Witch Hazel, Castor Oil or even lemon juice applied to the brown spots are a few other way to naturally get rid of your brown spots and leave your skin feeling smooth and healthy as well.