Tips to Whiten Yellow Nails Step 1 Buff your nails lightly to remove small amounts of yellow discoloration. Step 2 Dissolve a denture-cleaning tablet in water and use this to soak your nails for several minutes. Step 3 Squeeze fresh lemon juice into a small bowl ,then soak your nails for a few minutes. Wash your hands and follow with a moisturizer. Step 4 Make a paste of baking powder and lemon juice and apply a small amount to each nail. Buff lightly, then wash, dry and moisturize your hands and nails. Step 5 Make a paste of three tablespoons of baking soda and one tablespoon of 3% hydrogen peroxide. Use a cotton swap to apply the paste to the tops of your nails and underneath the tips. Leave on for five minutes, then rinse off. Tips & Warnings Always wash and moisturize your hands and nails after applying any of these treatments. Keeping your hands and nails well hydrated is an important part of keeping them healthy. Avoid over-buffing-while small amounts can remove stains and stimulate healthy nail growth, too much buffing can weaken your nails.