Time to w-o-r-k that upper body—watch exactly how to do push-ups correctly. 

For me, doing push-ups involves several key things: being on my knees (the standard modification), having trembling arms, dripping sweat onto my mat, and folding back into child’s pose many times. Push-ups are hard…and even harder when you’re doing them the right way.

And yet—according to superstar trainer Charlee Atkins, who reveals the push-up form secrets in our Well+Good The Right Way video series, a lot of people actually aren’t doing them correctly. “Let’s face it: Push-ups are not easy, and a lot of the times, most of us are doing them the wrong way,” she tells us.

What does the wrong way look like, exactly? She points out that the wrong way involves having your butt way up in the air. And oftentimes, your elbows will be pointing out—which will make it feel like the push-ups are easier. “But in reality, all you’re doing is setting yourself up for an awesome injury,” Atkins quips.

Here’s the deal—she says that push-ups are actually quite simple once you nail the correct form. Here are the three things to make sure of when doing them correctly:

1. Work from plank position: “Have your body create a moving plank,” says Atkins. Start in a plank position with your shoulders right over your wrists, middle finger pointing forward. Hands should be about mat-width apart.

2. Remain in a straight line: Rather than have your butt in the air, maintain a straight line from your head to your heels throughout the entire exercise.

3. Proper elbow placement: While Atkins notes there’s not a direct degree of where your elbows will be placed, know you want them somewhere in the middle—essentially extending out past your chest and shoulder area when you push up. “Your elbows move out, and come right back up as you push down and up,” she says.

Of course, different push-ups exist. Your elbows may be tucked in tighter if you’re doing tricep push-ups or a yoga push-up (AKA chaturanga), or they can go wider for a wide-stance push-up. But the instructions above are for your traditional push-up.

Need to modify? (“AKA, how to make them easier”, jokes Atkins). Add some elevation, like a box or a block underneath your hands. “Then you’re not so far from the ground,” she says. Everything else remains the same. Now drop and give me 20.

To round out your arm work, here’s a resistance band arm workout that’ll burn. And then get your sweat on even harder with this at-home HIIT workout courtesy of June’s Trainer of the Month, Meg Takacs.