The first thing that ever got me super into beauty was nail polish. I love painting my nails. I find it therapeutic and easy, it makes me feel good about myself with limited effort, and it isn't one of those things that's made inaccessible to us via random beauty standards. Most of the time, nails are just nails, no matter who has them.
The only problem with this, however, is that painting my nails continuously tends to leave them looking a little gross when they're eventually left bare. Because, while it isn't true that nails need to be left bare in order to "breathe" (because they obtain oxygen via your bloodstream and not the atmosphere) it's still true that your nails may need a bit of a break in order to keep them in their original colour. Turns out, painting your nails frequently, especially with red or darker colours, leads to serious staining. As in, your nails will go yellowish.
Don't be quick to retire those Essie bottles, though, because it's totally and painlessly reversible.
The first and most preferable step to having yellow-free nails is to actually protect them pre-nail polish application. This means taking time to bother with a base coat. If that sounds like too much of a mission for you or your nails are already stained (or you actually did put a base coat on but some nail polishes are just not having it), here are some solutions.
Buff it out
If you have strong nails and can afford to do so, a super easy and quick way to deal with stained nails is to buff them. I'd recommend using the lightest buffer possible first, because you don't want to damage your nails or thin them out.
Toothpaste and a toothbrush
This is a simple, effective way of whitening your nails. All you do is apply some whitening toothpaste to your nails. Then, rub away (gently) with a toothbrush or nail brush. You may need to repeat this one a few times for best effect.
Baking soda and lemon juice
In my experience, this is the best way to whiten your nails. All you need to do is mix up a tablespoon of baking soda with some lemon juice — just enough to make the mixture smear-able.
This is a little bit drying on skin, so if you're concerned about your precious cuticles, smear some Vaseline on them before applying.
The baking soda exfoliates the nail, while the lemon juice lightens up those stains.
Leave the mixture on for a couple of minutes and then rinse off to happy, shiny, like-new nails.