Madison Beer made a triumphant return home in August performing in front of 20,000 fans at the eighteenth annual Arthur Ashe Kids’ Day at the U.S. Open Tennis Championships, but it’s just a sign of things to come for the talented 15-year-old.

Beer wowed the crowd with a high-energy performance and joined an impressive list of alumni who have performed at the annual event, including Britney Spears, Rihanna, Demi Lovato and Justin Bieber. She called the nod “an honor” and said she enjoyed rubbing shoulders with the other performers, including Grammy-nominated country star Hunter Hayes.

She also won plenty of style points with her trendy outfit that’s suitable for all budgets. Her customized Ralph Lauren Ball Girl polo shirt, pleated tennis skort and American Apparel Stripe knee-high socks can all be purchased for around $150! Her clothing choices have become so talked-about, in fact, that numerous style blogs are dedicated solely to what she wears on the red carpet.

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“My style isn’t edgy, but it's on the edgier side. I just like to be myself and wear whatever I'm feeling that day,” Beer told Hollywood Take. "I prefer things that are comfy and casual. I'm a jeans and T-shirt girl most of the time. But my favorite accessory is a cute purse."

Beer has devoted a section to her website to blog about her fashion choices, which include tutus, turquoise jewelry and flannel shirts. Perhaps somewhat surprisingly, the flannel shirts are partially inspired by her love of ‘90s rock bands like Nirvana. She says their single “Lithium” as one of her favorite songs.

The adorable brunette is a protégé of Justin Bieber, who first took notice of her after watching some of her YouTube videos. Beer began posting videos of herself singing covers of popular songs in early 2012, when she was just 12 years old. Her cover of "At Last" by Etta James eventually attracted the attention of Bieber, who immediately took her under his wing.

After the video reached over one million views on YouTube, Bieber personally signed Beer to the record label he’s on, Island Records, and made an appearance in the music video for her debut single “Melodies.” She’s also now represented by his manager, Scooter Braun.

"He tweeted that video out to his millions of fans, which was crazy and surreal," she said. "He got in contact and I'm out in California now. I'm in the studio a lot, making lots of music and doing what I love. I couldn't be happier."

Beer has since released her second single, “Unbreakable,” and is currently working on her debut full-length studio album. The bubbly singer said she considers Bieber to be a mentor and that he’s been instrumental in guiding her through a somewhat difficult music industry.

"He's given me a lot of advice," said Beer. "He's just told me to always keep your head up and keep your eye on the target. It's the same advice I'd give to people trying to make it in music. Just follow your dreams and never give up. I never gave up and now I'm doing what I love every day."

But while Beer said she’s been enjoying all of the opportunities that her sudden fame has presented her, she remains focused on the task at hand. "I just want to keep releasing more singles," she said. "I'm listening to a lot of feedback that some people have. But I'm just really excited to keep making more music."

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