Dr. Pimple Popper on When She Wears 'Splash Guards' — and Why You Should Skip This Viral Skincare Trend (Exclusive)

• Dermatologist Sandra Lee, the viral sensation who famously pops the biggest cysts and manages other unusual skin conditions, returns to TV April 21 with her new Lifetime show, Dr. Pimple Popper: Breaking Out
• Lee reveals the skincare trend that she says can cause blackheads — and shares the best thing she's ever done for her own skin
• She sounded off on the worst pops, and the one that's a "unicorn blackhead"

Strange growths, unusual rashes and giant cysts that explosively burst —  Dr. Pimple Popper has seen wild things.

But through it all, dermatologist Sandra Lee treats her patients with empathy and kindness. “My dad's a dermatologist, and he told me you could be the smartest, most accomplished, most intelligent, published dermatologist in the world. But if you have a terrible bedside manner, your patients are gonna think you're not a good doctor,” Dr. Lee, 54, tells PEOPLE exclusively.

The viral sensation returns to TV April 21 with Dr. Pimple Popper: Breaking Out, her new Lifetime show that documents life in her California clinic, where she is now mentoring early-career dermatologists and medical student protégés.

“It’s an honor to be a mentor,” she tells PEOPLE. “I learned by watching others that I really loved and respected and saw how they treated their patients. Those are the people that I emulated when I became a dermatologist and developed my skills. So hopefully, they may learn some things from me,” she tells PEOPLE.

Ahead of the April 21 premiere of her new show, Dr. Lee shares with PEOPLE the best — and worst — skincare tips, office tools, and, of course, pops.

What’s the best thing you’ve done for your skin?

“Minimize being in the sun and wearing my sunscreen,” Dr. Lee tells PEOPLE. “That's the most important thing that I will always do. My mom looks great at her age.” While Dr. Lee says “genes play a huge role in how your skin looks,” she adds, “she stayed out of the sun.”

What’s your favorite skin tool in the office?

“I also have a giant comedone extractor that I've made into a ‘comedoneski’ cause it has shot glasses in it. Multiple people can take a shot,” she said, comparing the oversized dermatological tool to the popular bar trick where people take simultaneous shots out of a ski with shot glasses affixed to the top. The alcohol of choice, she says, is tequila or vodka.

What social media skincare trend would you never try?

“I don't really love the beef tallow thing,” Dr. Lee said of the viral trend of using the rendered fat on your face. “You don't know what is in that beef tallow. You could be applying things that —  especially if you have a cut or opening in your skin —  could cause some problems there.” Besides, she adds, “I'm not into rubbing myself in lard. That's how you get blackheads and whiteheads, you know.”

The PEOPLE Puzzler crossword is here! How quickly can you solve it? Play now!

What’s the best pop?

“A big dilated pore of winer, which is like a giant blackhead,” explains Dr. Lee, who describes the clogged pore as “a plug” in the skin. “You just have to numb it and wiggle it a little bit with a little tweezer, and they just pull out. There's no bleeding. They're like the perfect unicorn blackhead.”

What's the worst pop?

There isn’t one specific pop that stands out as the worst, Dr. Lee tells PEOPLE; rather, it’s a category of pops. “The worst pops are the ones that have been infected or inflamed multiple times with scar tissue and so they're very hard to get out completely,” she says. “You guys don't get smell-o-vision so much, but those can more likely have an odor. It's really embarrassing to the patients, certainly, so we don't acknowledge that. We just wear our splash mask.”

But, as she adds, they are “the worst kind of pop because they're also under pressure. One squeeze can make something get into your hair. When that happens, that's like the worst day because you want to take a shower.”

Dr. Pimple Popper: Breaking Out premieres April 21 at 9 p.m. ET on Lifetime.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.