• Buttermilk is one of the most widely used natural skin bleachers. Therefore, all you have to do is pour a little amount of it in a medium bowl. Soak a cotton ball in the lotion and wipe the dark spots and the affected areas with it. Let the buttermilk on for at least 10-15 minutes. Finally you can easily rinse off the facial with lukewarm water. Experiment with this top skin whitening remedy more times per week to see the positive results.