The star told PEOPLE that she’s long been taking these baths “for all things”

Jessica Biel’s epsom salt bath went viral on on May 6 before she even hit the Met Gala steps, but the star had been relying on the wellness ritual long before the buzzy moment.

“Epsom salt baths is a tool I love and use for all things, after traveling, sore muscles, of course, magnesium, absolutely, to sleep well, to de-stress, to, you know, just feel confident in your body to go to a big event like the Met Ball, which is what I was utilizing it for,” the 42-year-old actress tells PEOPLE exclusively.

Prior to the Met Gala, Biel offered fans a look into her getting-ready process, which included soaking in 20 pounds of epsom salt in hot water the night before. “For real,” she said in a TikTok video as she showed herself pouring the salt into the bathtub.

Biel shared another behind-the-scenes moment on Wednesday, May 8.

“Hey, you guys,” she said while taking a bite of salad in a TikTok video. “I’m supposed to be getting dressed for the Met, but I had to eat something.”

She explained that she was “hiding in the corner of my room” as members of her team tried to make sure she was dressed on time.

“Everybody’s, like, knocking on the door, ‘You gotta get dressed!’” Biel said.

“I’m just trying to tell you, snack first, eat first!” she continued.

On the Met Gala red carpet, Biel looked regal in a pink silk faille gown and cape by Tamara Ralph Couture, which were embellished with striped coque feathers and crystals. The ensemble took 320 hours to make.

When it came to choosing her look, Biel shared that while pink isn’t her favorite color, she gravitated toward the dress.

“It’s actually not necessarily the color I am often drawn to, but this particular pink and this particular dress just was the one for me,” she tells PEOPLE.

Jessica Biel at the 2024 Met Gala.JAMIE MCCARTHY/GETTY

The Candy alum also said that the most “memorable” part of the annual fundraising event happened once she finally reached her table after seeing the exhibit at the Metropolitan Museum of Art.

“I finally sat down on my chair and realized that the person sitting next to me, who is the lovely Donald Glover, didn’t have a seat anymore because my dress was sitting in his seat,” she recalls. “I said, ‘I’m sorry, Donald, we’re going to do this together. We’re going to get you this seat.’ As I was pulling and yanking and throwing this dress and it never stopped coming.”

She continues, “And he said, ‘Don’t worry, I’m just going to come back next year.’ He was so nice about it. He said he finally pulled up a chair. So we sat between my dress and enjoyed our dinner like that.”

Biel, who shares two sons, Phineas, 3½, and Silas, 8½, with husband Justin Timberlake, is gearing up for the release of her new book, A Kids Book About Periods. Coming out on May 14, the project is in collaboration with the nonprofit organization PERIOD. and seeks to de-stigmatize discussions around menstrual cycles.

“People don’t talk enough about periods,” Biel said in a press release. “I’ve always felt strongly that we need to normalize the discussion around periods and as a parent, writing this book felt like an organic way to engage kids in the conversation from early on.”