Take your orange skin and dry it in the sun until really brittle. If it's rainy or snowy or just not sunny, you can dry it inside until really brittle. Be careful of fruit flies and bugs. Once dry, chop the orange peel into tiny pieces so that it's almost powdery though still grainy.

Take some milk and add it to the ground orange peel to make a pasty texture. Adding too much milk will make it watery, and not adding enough will make it dry and rough. Mix this paste well.

Now wash your face! You can use this face wash weekly to brighten your skin, but know your skin and whether or not repeated use will hurt it.