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Made famous by industry luminaries Kevyn Aucoin and Laura Mercier, tightlining is the technique of drawing eyeliner inside the lash line, on the waterline. It provides an imperceptible definition and structure to the face by filling in any gaps in the lash line and creates contrast with the irises, according to celebrity makeup artist Suzy Gerstein.
"That contrast helps really define the eye without making it look made up. Done properly, it should not look like you are wearing eyeliner at all," she told HuffPost. "Your eyes should just look bigger and more twinkly, but to the naked eye it will not be obvious why exactly they look so amazing."
Gerstein notes that the late makeup artist Way Bandy used this technique in his '70s and '80s makeup manuals before it even had a name. "Tightlining is great for hooded eyes and other eye shapes that tend to look overly made up or droopy with a thick, visible band of traditional eyeliner," she said. "The trick is also a fantastic way to intensify a smoky eye or anchor a wash of pale shimmery shadow."
So how exactly do you tightline?
Gerstein recommends positioning a mirror on a flat surface so you're looking down into it. "Gaze down into the mirror with your chin angled upwards and eyes staring downwards to allow you to get into that sweet spot right in the lash lines. Using your non-dominant hand, pull gently up on the lid and use your other hand to tightline," she said.
Dip a flat makeup bush into a black liner product. Pro tip: use just enough pigment to coat the bristles on both sides -- it's always easier to add more. Gerstein likes to dip both sides of the brush in the product and then remove a little bit with her hand to remove excess.
"Then, holding your brush vertically, wiggle the tip of the brush gently into the top waterline," explains Gerstein. "Move across the eyelid, from the outer to the inner corners, wiggling as you go." Unless your eyes are wide set, this makeup artist suggests stopping before you get all the way into the inner corners to avoid making the eyes look closed.
"You'll want to apply the liner anywhere you have lashes because remember, the objective is to make it appear as if the lashes are more lush and full than they are, not that you're wearing eyeliner," she said.
Next, clean up any smudges with a Q-Tip dipped into water-based makeup remover like Koh Gen Do Cleansing Spa Water. Allow the liner a few seconds to dry before you curl lashes. Gerstein recommends finishing with a couple generous coats of a volumizing mascara to frame the eyes beautifully without adding the weight of excessive product.
Want to try your hand at tightlining? Click through the slideshow to shop Gerstein's eye makeup product picks.