Have a Friend Who's Struggling? Brittany Snow Shares Her 'Life-Changing' Tip

For Brittany Snow, bringing her "mental health awareness and letter writing experience" site September Letters to life — with the release of her inaugural book, September Letters: Finding Strength and Connection in Sharing Our Stories — has been the ultimate full-circle moment.

As a teen, the Pitch Perfect actress struggled with anorexia, depression, and self-harm for nearly a decade. It wasn't until she came across an article in a fitness magazine detailing one woman's similar experience that Snow felt hopeful that she, too, could overcome what she deemed "obsessive, compulsive, disordered thinking."

She ripped out the page and kept it in her back pocket for months, but wasn't sure she was ready to go public with her struggles as talking about mental health was still quite stigmatized. But in 2007,Snow opened up about her own struggles in an essay for PEOPLE — and years later, met a girl in a coffee shop who had kept Snow's essay in her own back pocket in a full-circle moment.

"It was one of those moments where I just felt like I knew that this had to be made into something, where our stories connect us," she recalls to PEOPLE. "So, I went to my friend Jaspre [Guest, cofounder of September Letters] and said, 'You know? I've always wanted to do something with this idea that if you tell your story, you could be helping not only yourself but someone else.' That's how September Letters was born, and now we have a book with sort of the same concept."

Snow's September Letters book, which she worked on with Guest, compiles essays, bulleted lists, interviews and more, contributed both by everyday people and public figures including Kid Cudi and Maria Menounos. Despite the different formats, however, each penned submission shares a common goal: to help the writers and readers feel less alone. Snow tells PEOPLE she found the diversity of contributions "really beautiful."

Snow, who most recently made her directorial debut with this year's Parachute, has come a long way since her teenage years. But no human is immune to the emotional ebbs and flows life has to offer. Snow, like the rest of us, still experiences bad mental health days from time to time. The difference? She's now better equipped to handle them, thanks in part to the unwavering support from her close friends.

"There are so many times where, in the past year, I just called some of my best friends, and they were just there," she tells PEOPLE. "They just stayed on the phone with me. It was life-changing, to be honest. I think it was just so beautiful to know that somebody was just going to sit by the phone."

She adds, "I think that people knowing there's a friend there to take them to a therapy session, or go to the park with them and sit there, or research things on their computer that they might need help with — I think that's so much more valuable than telling someone what they need to do. That has been really helpful for me."

And when you're in doubt of how to approach a friend who may be having an "off" day, Snow recommends making another thoughtful gesture.

"I've bought a lot of flowers in my life," she says. "Everybody likes flowers."

September Letters is available for pre-order, and is out on May 23rd.

If you or someone you know needs mental health help, text "STRENGTH" to the Crisis Text Line at 741-741 to be connected to a certified crisis counselor.