Reaching for a bottle of nail polish only to find out that it's gone clumpy is disappointing, to say the least. The good news? Due to all of the solvents polish contains, it pretty much remains bacteria-free. However, the solvents can evaporate over time, and that's what gives you thickened polish. Bummer. Generally speaking, your nail polish should last you about one year before expiring, but I've also heard anywhere from one-and-a-half to two. So, how can you prolong the shelf life of your favorite shades? Here are some tips.

• Air out: Each time you polish, wipe residue off the threaded portion on the top of the bottle to ensure tight closure. Tight closure is a must to prevent the polish from drying out.
• That's not hot — Store nail polish in a cool, dry place. Warm environments can cause the color to alter and polish to separate.
• Stand up straight — When storing, place the bottle in an upright position to prevent the pigments and solvents from separating.
• Stay cool — Many people like to prevent clumping by refrigerating polish to preserve it, although others argue that this technique doesn't work because it changes the chemical texture of the product. I say, chill out.

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