Ella Purnell, the Yellowjackets, Army of The Dead, and Sweetbitter star, is one of the most accomplished young actresses today. And she's also got serious star power. While doing a Q&A on his Instagram stories, musician Max Bennett Kelly was asked "Why are you so hot?" "No u @ella_purnell," he answered, posting a photo of her in a hot pink bathing suit at the beach, which she reshared. How does she stay so fit? Read on to see 5 ways Ella Purnell stays in shape and the photos that prove they work—and to get beach-ready yourself, don't miss these essential 30 Best-Ever Celebrity Bathing Suit Photos!

Purnell always sticks up for herself, and makes sure that she is comfortable in every role she plays. She says that she is vocal about her wardrobe and costumes on set. "Being in your early twenties, that shit comes up all the f***ing time and you have to be really firm about it from the start," Purnell said to The Independent. "So I came in hot, saying, 'I'm not gonna wear high heels! I'm not gonna wear a push-up bra!'"

df44d9eab23ea271ddde7545ae2c09ec

Purnell is an advocate for mental health awareness. She revealed to Standard that she previously self-harmed, and wants to encourage dialogue on it, and getting proper help. "Self-harm is not about attention — I hid [my scars] for six months, wore long T-shirts, covered them up with make-up. It's about punishing yourself, for people who dislike themselves or suffer from insecurity or self-doubt.

Purnell tells Standard that she reached out for help to deal with her mental health and self-harm. "They want to hurt themselves because they think they deserve it: that's where I was at. I had to work very hard to remove my trigger points and to create a safe space so I wouldn't become tempted to get back into it again."

Purnell is an avid writer. She tells IntoTheGloss.com that she started writing a book about her mental health with her therapist. "I started writing a nonfiction book on mental health with my therapist. We're approaching the subject from two points of view—there's a side of it that's based on personal experience, but then there's another side that's scientific."

Purnell puts herself first, and always takes breaks from her busy schedule. She tells IntoTheGloss.com that she likes to take days to relax. "For me, self-care is about committing to myself. The actual bits and bobs matter less than actually carving out one hour a week and dedicating that time to myself.