Karanikolaou has teamed up with swimwear brand, TJ Swim, to create her own line, inspired by the colorful suits that cover her Instagram feed.
“I’m very picky with my swimwear and the designs that I think are flattering,” Karanikolaou tells PEOPLE exclusively ahead of the launch. “For the line, I was very particular with how everything fit and designed it to be flattering on every body type, not just mine. I wanted everyone to feel and look good in it.”
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Featuring 12 ’90s-inspired bikinis, the collection pulls inspiration from the suits Karanikolaou wears daily, including the neon string bikinis that her and Jenner repeatedly match in.
“We love to twin,” she says. “It’s a cute, fun thing we started and now we just run with it. The twinning never stops!”
She continues: “I’m a string bikini girl. I like minimal tan lines. I think strings are so sexy and I love how they hang down the side.”
But the Instagram star didn’t create a swimwear line without enlisting her friends, including Jenner, to weigh in on the designs.
“I made all of my friends come for a ‘try-on party’ and test all the samples so I could see how it looked on each of my their bodies,” Karanikolaou explains. “I took everyone’s feedback and put it back into the designs and this is what we have now. The process was definitely a group effort and we collectively came up with it together. I’m really happy with how it came out.”
Since the Los Angeles-native she spends most days at the beach, she put a huge emphasis on creating versatile swimsuits that can be worn poolside, and beyond.
“We created a top you can wear four different ways, which I thought that was a really and cool idea for someone who can only afford to get one suit. I definitely wear this as a cute top with high-waisted pants or under something sheer,” she explains. “We also made the bottoms go in a V-shape. It highlights people’s curves and doesn’t bunch up in the front.”
Not only does Karanikolaou want to create flattering swimwear for her fans, but she wants to feel as confident as she does in her bikinis.
“The number one thing people do is compare themselves to others and that’s when people start to become less confident,” she says. “I want people to love the skin they’re in. Everyone is made differently for a reason and no one else is like you.”
Start shopping the Stassie x TJ Swim collection on Nov. 5 at tjswim.com.