1. Make a paste of a mixture of yogurt and crushed walnuts
Apply evenly on the neck. Use a scrubbing. This mixture can whiten the neck skin and remove dirt and a layer of dark skin on the neck. Repeat this three times a week.
2. Applying cucumber juice on dark skin around your neck
3. Take one tablespoon of chickpea flour, few drops of milk, and a few drops of lemon juice and a pinch of turmeric powder
Mix these ingredients together and mix and apply it on your neck. Put this mixture on the dark neck for 30 minutes and rinse with warm water and wipe with a towel.
4. Take a potato, 5-10 tsp of fresh milk and a teaspoon of coconut oil
Mix together to form a paste. Before putting this paste on your neck, wash your neck thoroughly and dry with a towel. Once dry then smeared on to the neck and leave on for half an hour. Then wash off with warm water.
5. Many eat green vegetables
Source : http://tipscarakecantikan.blogspot.com/2013/02/cara-memutihkan-kulit-leher-gelap.html