Here is the entire procedure in details:

Chop a medium-sized onion into pieces. Then, mix it with apple cider vinegar into the blender until you get smooth, homogeneous mixture.

Next, soak a cotton ball in it and rub the affected skin areas with it.

For best effects, you should repeat this daily for a month. Yet, the effectiveness of this natural remedy will surprise you, as the age spots will start disappearing after the first 7 days!