You know that girl in your spin class who has the most amazing lashes, but never seems to get streaky or smudgy (even after 45 minutes of intense sweating)? She probably has eyelash extensions. You could ask her about them after class…or you could consult this guide.

RELATED: 13 Surprising Things That Might Happen If You Get Eyelash Extensions

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What Type of Lashes Should I Get?
The most common types of lashes available are made with silk, mink or synthetic materials. There are obvious pros and cons to each type (silk lashes are shinier while mink lashes are lightweight), but if you’re a first timer, synthetic lashes are often recommended as they are the most cost-efficient and the least likely to cause an allergic reaction.

What About the Curl Types and Lengths?
In order of least curly to most, you can usually choose from a J, B, C and D curl—and lengths typically vary from 8 mm to 14 mm. So how do you make sense of this jumble of letters and numbers? Ask your technician to vary the lengths and curl of the lashes so they’re customized to your eye shape and preferred aesthetic (for instance, Alicia Keys versus Kim Kardashian). At most salons, you aren’t approached with said jumble of letters, but you should have a frank conversation with your technician about how you want them to look.

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What If I Have Sensitive Eyes?
Prior to your first appointment, you should have a spot test done to make sure you aren’t allergic to the lash adhesive. On that note, if you have a known silicon allergy, make sure to let your technician know before she begins so she uses medical tape instead of under-eye patches (which are typically made of silicone) during the application.

How Long Does the Whole Process Take?
Your first appointment could take anywhere between an hour and a half to two hours. During this time, you’ll be lying down on a table with your eyes closed and the aforementioned silicone patches will be placed underneath each eye to keep the bottom lashes out of the way. Depending on the number of natural lashes you have to work with, your technician will carefully attach the extensions to the base of your own hairs one by one.

Does It Hurt?
Not at all—rather, in the right hands, it shouldn’t. In fact, many people fall asleep during their appointment. (Can’t fall asleep? It’s also a good time to catch up on some podcasts.) 

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How Much Does It Cost?
Prices for a full set can cost between $150 and $300, depending on where you live and which salon you go to. (We’ve even heard of some New York salons charging upwards of $400.) For any subsequent appointments (or fills) you can expect to be charged between $85 and $120.

What’s the Upkeep Like?
Most places recommend that you go back for a fill every two to three weeks. However, depending on how skilled your technician is and how careful you are with your eyes, the lashes can last for up to five weeks. To get more mileage out of your extensions, avoid steam or water for the first 24 hours after getting them, and keep any oil-based cosmetics off your lids (as both can break down the adhesive and cause them to fall off faster). Also, be careful not to rub your eyes or run high-pressure water over them during the duration of your extensions.

What If I Don't Want Them Anymore?
When properly applied, each extension should last until your natural lash sheds (typically between three to six weeks). So you can either wait it out or ask your technician for a removal (which should take only about 15 to 20 minutes and cost about $25 to $50). Whatever you do, don’t try to pull them off yourself as that's how you end up with sparse lashes. 

RELATED: The Foolproof Way to Protect Eyelash Extensions

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