1. Keep the Color on the Top Lid Only
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You don't want to outline your entire line with blue liner, or it'll look too intense.
2. Use Black Liner, Too
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Instead of just using blue liner, you can start by using a black liner close to your lids and then use some blue up above it.
3. Highlight Your Tearducts
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you use a light, sparkly aquamarine liner, then you can put it by your tearducts to act as a highlighter.
4. Press Lightly on the Lower Lash Line
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If you're dying to place some liner on your lower lash line, then you can. Just don't make it look heavy.
5. Wear False Lashes
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You can make your eyes look even more intense by wearing them with long false lashes.
6. Use Grey on Your Waterline
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You should use a "grey pencil liner along the waterline for balance."
7. Only Line a Third of Your Eyes
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Instead of placing your liner all around your eyes, simple "line the upper and lower lash lines about a third of the way across with blue eyeliner."