Yes, even if you're past your acne-prone years. As you go about your day, your face picks up environmental debris, like dirt and other pollution-related skin saboteurs. Who wants to sleep with that plus makeup sitting on their face? Not only is it icky to think about, some of these particles can actually get into your pores and speed up the aging process. (You can read more about how pollution affects your skin here.)

Have you ever heard the phrase "worrying will give you wrinkles?" Turns out, this is pretty accurate. Stress damages your cells, which leads to premature lines and wrinkles (among other things).

Sometimes your day/week/month/year feels too busy for anything remotely resembling a social life. Meeting up with friends and "bonding" not only helps relieve stress; it can also keep your brain healthy as you age.

You can also unwind sans company by taking some "me time" -- experts say that incorporating soothing rituals into your routine can help diminish stress.

It isn't always your skin that shows the signs of aging. Dull, lackluster hair can be another dead giveaway to your age, and can make you appear older than you are. Keep your hair shiny, smooth and soft by using a nourishing hair mask, like Kerastase Masque Densite, $62, once a week.

If eyes are the windows to your soul, then your hands, neck and décolletage are the windows to exactly how old you are.

If you only apply your anti-aging serums and moisturizers to your face, that's (not shockingly) the only place you'll see the benefits. Why spend money on achieving a line-free face if your turkey neck is just going to give away your age? In addition to your face, smooth your serums and moisturizers down your neck, over your décolletage and even on your hands to keep everyone guessing your age. (Read more about how to keep your hands from giving away your age here.)

As you age, your metabolism starts to slow. Getting in at least 30 minutes a day of exercise can help boost your metabolism -- not to mention, studies have shown that doing weight-bearing activities, like walking and jogging, can help increase bone density.