So, what is it, how often should you use it, and where should you apply?

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Woman Applying Primer
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When it comes to our list of beauty expenditures, it's oftentimes easier to justify the lipstick, anti-aging, mascara, and good concealer. As for the primer, well, it can be similar to buying deodorant—useful, but a tad uninspiring. I used to feel that way, until IT Cosmetics Your Skin But Better Oil-Free Primer+ came into my life. (Read our review here.) Since I starting priming before foundation, my makeup has never looked better and it actually stays put—what a novel idea.

The 3 o'clock mirror check: The one you dread, knowing full well that your makeup will have lost its luster, your under-eye circles will have made their mid-afternoon reappearance, all while your blush has somehow vanished into thin air. This does not have to be your fate. It wasn't until I found a good primer that I finally beheld the joy of gazing into the mirror late in the day to discover I wasn't in need of a full-face redo. I've tried a number of primers over the years and none has worked quite so well as the IT version I mentioned above. So, to find out everything I ever wanted to know about primer, I went straight to the source: IT Cosmetics' Director of Education, Jessica Ross.

To start, Ross advises that primer should only be applied to a clean face. When primer is put on top of skin that hasn't been recently cleansed, it has the potential to increase the likelihood of a breakout since the formula is designed to smooth out or fill in pores, thus holding in any impurities that might be present before the primer is applied.

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You'll only need a dollop about the size of a nickel. "I recommend using primer all over the face with a focus on the t-zone where we have the most redness, pores, and hyperpigmentation," Ross says. Next, you can either apply your foundation, or skip it altogether. In addition to smoothing out the texture of the skin, many primers are designed to bring a host of additional benefits. Some provide anti-aging effects, others add a boost of hydration, while we've even found some to work as a natural-looking base that eliminates the need for foundation altogether—like Your Skin But Better Oil-Free Primer+. Ross suggests using it every day, though you can certainly reserve use for occasions that will require a fresh face for hours on end (holiday party season, anyone?).