I thought I was incapable of whistling. Then I learned how.

For a long time, I considered myself a person who was simply incapable of whistling. Then I taught myself how.

Lots of non-whistlers think of whistling ability as a genetic trait, like attached earlobes or blue eyes. They’ve never figured out how to whistle, and they assume it’s simply beyond their capabilities.

But there’s no real evidence of any factors, genetic or otherwise, that might prevent someone from learning. And there are tons of people, like me, who’ve taught themselves to whistle, even at relatively advanced ages.

With that in mind, I spoke with whistling champion Chris Ullman (yes, there are whistling competitions and champions) for tips. “If you put time into it, you might be able to overcome a lifelong inability to whistle,” he says. “But like anything else, it takes practice.”

There are three main variables you need to figure out to whistle: the shape of your lips, the amount of air you’re blowing through them, and the position of your tongue. Ullman recommends trying to isolate and perfect each one individually, starting with the lips.

For the standard form of whistling (technically known as pucker whistling), you want pucker your lips slightly, making a small opening that you’ll force air through to make the sound. “Ultimately, you need a channel that the air is focused through. It can’t be too diffuse,” Ullman says.

People’s pucker shapes vary. Most are roughly O-shaped, while Ullman says his expert whistle is the result of an “inverted pentagon.” For a rough idea of the right type of opening, say the word “two” and leave your lips in the position they’re in at the end of the word. Practice in front of a mirror, without trying to whistle, just to get a sense of how to pucker your lips in the right position.

“The tongue is a channeling mechanism,” says Ullman. “It helps take air that’s coming out of your lungs and focus it so there’s a constant pressure, and it’s directed right at the hole in your lips.”

To do this, press the tip of your tongue just below the bottom of your lower teeth. You’ll also want to curl the tip of it slightly upward.

Later on, once you’re able to whistle, you can use your tongue to change the pitch of the note. The tip will stay on the bottom of your mouth, but by flexing the middle of your tongue slightly and bringing it upward, you’ll be able to alter the shape of your mouth chamber, creating higher or lower whistling notes. For now, though, just concentrate on holding your tongue in the right spot.

This might be the trickiest step, and getting a feel for the right amount of air to blow is often the thing for non-whistlers have trouble grasping.

“Blow very gently,” Ullman says. “It’s not a power thing — it’s a finesse thing.”

He compares it to playing a recorder: If you blow too hard, you’ll get no sound at all. The key is blowing a relatively small amount of air — the amount that comes out when you exhale very slowly — but pushing it through a small opening between your lips.

The big challenge in learning how to whistle is that all the action is happening inside in your mouth. “If I were playing violin, someone could look at my fingers and say, ‘Your vibrato is off for the following reason,’” Ullman says. “You can’t do that with whistling.”

Consequently, the only way to really get better at it is by figuring it out yourself. That might sound daunting, but I did it by initially making a quiet, halfway-whistling sound and noting how my lips, tongue, and breath felt when I did so.

Over the course of a few weeks, I practiced making that sound over and over, trying to replicate the exact mouth position and noting what I had to do to make it sound clearer. Once you get it, the feeling of producing a good whistle is very distinctive, and it’s easy to return to it and improve on it.

By doing consciously working on it, I eventually made the sound I could produce much clearer. I’d gone from a non-whistler to a whistler — though certainly not an expert like Ullman.

Ullman — who’s performed with the National Symphony Orchestra, on the court at NBA games, and in the Oval Office — treats his whistling much like an opera singer treats her voice. Ultimately, he says, it’s not all that different from proficiency with another musical instrument: It takes a lot of hard work.

Maintaining the proper pucker position can tire out the lip muscles, so he keeps them in good shape by whistling for long periods of time. “I once went on a road trip where I whistled for five hours every day,” he says. “By the end of the day I could barely even talk.”

Getting lots of practice at switching between different notes — by flexing and altering the position of the tongue — is also essential. “One of the things that really makes for quality whistling is the ability to move between notes while keeping air at a constant pressure,” Ullman says. He develops this ability by trying out new songs, stretching his range.

But he also has a few specific rules that he follows to maximize each performance. He brushes his teeth before professionally whistling, in order to clear out any possible debris that might interfere with a clear noise. He also drinks ice water right before performing, in order to constrict his lip tissue, so it provides a smooth surface for air to flow over.

Finally, he has one particularly unusual habit aimed at keeping his lips as firm as possible. “I have a no-kissing rule for 24 hours before every performance,” he says. “It helps to sustain a crisp pucker.”