Hydrogen Peroxide:This will instantly whiten and Brighten nails, Just take a cotton swab or cotton ball and soak it in the the solution, run the cotton swab over the nail bed and you will see it will lighten into a few shades.
Water and Baking Soda Bath: This should be done every couple of months to have a nice and bright white nail bed, this will also keep them healthy.Just mixed half a cup of water with a table spoon of baking soda stir this cloudy mixture and have your bare nails soak in it for twenty minutes. you nails will be a bit dry after this. So be sure to throughly wash your hands and apply a nail oil onto your nails. If you can't find already made nail oil, you can use rose oil or sweet almond oil.
So no need to worry anymore if you continue this routine you will have beautiful nails. So go and be the best you.
(The nails above are made by me and are called "Orange Graffitti" and "Golden Flower")