So you’ve decided to grow a beard. You’ve got a nice crop of stubble going, and now you need to clean up your neck. Which means it’s time for that first big decision: Where does your shave end and your beard begin?

“If your chin or your jaw isn’t really there, a beard can bring some shape to the face,” says Jessica Candia, a hairstylist at Brooklyn’s Persons of Interest barbershop. “It’s very helpful, but it can get tricky.”

So you’ve decided to grow a beard. You’ve got a nice crop of stubble going, and now you need to clean up your neck. Which means it’s time for that first big decision: Where does your shave end and your beard begin?

“If your chin or your jaw isn’t really there, a beard can bring some shape to the face,” says Jessica Candia, a hairstylist at Brooklyn’s Persons of Interest barbershop. “It’s very helpful, but it can get tricky.”

We woke up like this.

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“If you naturally taper under the neck already, a fade on the neck cleans it up without adding hard lines,” says Candia. “But with a lot of guys, hairier guys, the chest doesn’t separate from the neck hair without shaving.”

And when you’re shaving, even the most well-intentioned neckline can raise your beard up too high. The good news is, once you know this rule of thumb, you’ll never do that again.

Take your index finger and point to your Adam’s apple. Now slide your finger up to the top of your Adam’s apple, where it meets your neck. Think of it like balancing your finger on top of that little nub of cartilage (or whatever it is).

For most guys, including facial hair chameleon Chris Daughtry (below), this is the natural boundary between under-chin and neck.

Channeling the Dean… #bathroomselfie #jamesdean #hairenvy

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Now it’s time to trim along this boundary. When you tip your head back, the neckline should look fairly straight, running from one corner of your jaw to the other.

“Follow the line around without rounding too much,” says Candia. “It shouldn’t be a V—there should definitely be hair under both sides of the jaw.”

Use either your normal razor or a small trimmer—the neckline requires neat work. But don’t worry. If you screw it up, it’s fixable. Give your whole beard a short trim, resume shaving where the line should be, and let the boundary area grow back in.

Hello Bojack season 4. I see you. 🐴🍷💊🎬🎭

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A beard generally grows about a half an inch a month, but thanks to the contrast with your bare neck, even a couple weeks’ growth makes an impact. Relax. Breathe. Your under-chin will look like Aaron Paul’s (above) in no time.