By Mary Sollosi
Updated September 03, 2015 at 12:00 PM EDT

Fullscreen Live’s “Girls’ Night In,” which will unite six popular YouTube personalities on a month-long, 20-city live tour, kicks off on Sept. 22, and EW has an exclusive behind-the-scenes look at the tour’s first promotional video.

We visited stars Andie Case, Meredith Foster, Eva Gutowski, Alisha Marie, Meghan Rienks, and Mia Stammer, who have a combined following of almost 13 million subscribers, on the set of a short video they made to promote “Girls’ Night In.”

The girls were all already friends before joining forces for the tour with the exception of Case, the group’s only musician. “Of course we had to have a beautiful voice to entertain us,” Gutowski says, adding with a laugh, “to drown out our voices!”

Case and her two bandmates had been playing together for a while and doing local shows when they first uploaded a video to YouTube, a cover of Demi Lovato’s “Heart Attack.” It got a great response, so they started posting videos every month. “It kind of blew up,” Case says, “and everything kind of happened by accident, but I’m happy that it did.”

The rest of the gang are lifestyle personalities. Most started out with makeup tutorials and haul videos, and have grown to post more advice videos, DIYs, and “collabs,” often with each other.

The young women, who are all in their early 20s, met previously at YouTube events like VidCon, the mention of which makes them all giggle. “It was harder to recover from VidCon than it was Coachella,” Rienks says, evidently exhausted by the very memory. “I’m so not kidding.”

The “Girls’ Night In” tour will not take the form of a panel discussion, like the events at the Internet celebrity convention, but will more closely resemble the content the YouTubers are already famous for. “We kind of wanted it to be like videos in real life,” Marie says about the tour. “It’s cool, because you see the unfiltered versions,” Rienks adds.

On set, “Rollin’ With My Homies” plays in the studio as the ladies get their makeup touched up. Would Cher from Clueless would be a YouTube celebrity if she were in high school 20 years later? Maybe, but she might not hang with this crowd: The “Girls’ Night In” squad preaches against the pressure for physical perfection, and certainly would never try to instruct the “adorably clueless” in the ways of high school popularity.

“My goal for my channel is to inspire girls to love who they are and be confident in who they are,” says Foster, who started posting makeup videos after becoming “obsessed” with the YouTube beauty community. “I just want them all to know that no matter what anyone says, you are beautiful.”

That mission is consistent among all of the young women, who variously described their personal brands as “quirky,” “easygoing,” “optimistic,” but above all, “real.”

“I think the thing about the type of videos we make is, we try to be as relatable as possible,” Stammer says. She got her start in the YouTube world as a fan, and started making videos from there. “It looked fun,” she says. “It looked — not easy, but it looked like something everyone could do.”

The girls arrange themselves around the set, which looks like a teenage girl’s bedroom; colorful posters hang over a big, white bed with fairy lights draped across the headboard. Rienks flops down on the bed. “Nailed it!” She cries, apropos of nothing. “That’s my line,” she clarifies.

Rienks loved acting in high school, which indirectly led to YouTube career. “I got mono,” she says, “and I was supposed to go to theatre camp, and I couldn’t.” Stuck at home, she thought she’d try making videos. “I thought YouTube was a website for beauty and fashion,” she admits. “I knew nothing about it.”

Gutowski started blogging her freshman year college, and transitioned to YouTube when her readers started asking for videos. “So then I was like, what’s this YouTube thing?” she recalls. Marie, too, says she “randomly stumbled into it.”

All six women, it seems, began making YouTube videos with no intention of becoming Internet personalities — a title that didn’t even exist when a lot of them started. “I never knew it was a job, or a thing you could do full-time,” Rienks says. “I was like, this is the Internet; this is where you get lost at night.”

The YouTubers have been in the studio all day, but their energy and enthusiasm never waver. In between takes, they giggle and goof around on set, singing, dancing, beatboxing, and occasionally shouting, “Nailed it!” (Rienks’ favorite line does not, unfortunately, make the final cut.)

“We see our subscribers as our friends,” Stammer says — and they want to show their friends a great time. “I just want everybody that comes to the tour to just leave feeling really good about themselves,” Gutowski says. “Motivated to, from that night forward, just live with a positive attitude.”

Check out the girls’ first tour video below. Fullscreen Live’s “Girls’ Night In” tour kicks off Sept. 22 in Anaheim, CA. Tickets are available now.

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