This 35-year-old makes 6 figures designing gameday footwear for athletes like Drew Brees — and that's just his side hustle

Photo courtesy of @SolesBySir

Marcus Rivero was sitting in his kitchen in 2012 when he found himself panicking.

He was personalizing a pair of sneakers for then-Miami Dolphins cornerback Nolan Carroll, who'd reached out after he saw Rivero's work in a friend's Instagram post. Rivero was eager to design something stylish for Carroll, his first pro-athlete client, but the assignment was not going well. He had brushed nearly 20 layers of paint over Carroll's red, white and black Jordans. He texted him a photo, and the football player was less than enthusiastic.

Disappointed, Rivero threw his phone down, accidentally knocking over a jar of acetone in the process.

Photo courtesy of @SolesBySir

He grabbed a kitchen towel and began to frantically wipe off the mess that now covered part of Carroll's shoe. The result was a marbled, rusty-looking green and gold effect, reminiscent of the weathered facade of the Statue of Liberty.

"When I wiped the shoe, what came out was gorgeous," Rivero tells CNBC Make It. He sent Carroll a picture, and the football player texted back the heart-eyed emoji.

"I purposely dropped acetone on the second shoe, and I kept that a secret for, like, five years."

Photo courtesy of @SolesBySir

Soles By Sir, Rivero's now seven-year-old Miami-based business, has made a name for itself designing custom cleats and shoes for athletes and celebrities. The company's custom shoes sell for anywhere from $300 to $1,500 per pair, and Rivero says he now makes between 1,200 to 1,500 pairs a year. His most expensive pair ever sold for nearly $5,000, and auctions of his game-worn shoes have fetched a little over double that.

Dwyane Wade sports custom shoes made by Marcus Rivero of Soles By Sir.
Photo courtesy of @SolesBySir

Carroll was his first big client but Rivero, now 35, has since worked with superstar athletes who he says include Tom Brady and Dwyane Wade, as well as designing the boots for Conor McGregor during his 2017 record-viewing boxing match, "The Money Fight," against Floyd Mayweather Jr. (Representatives for Tom Brady and Dwyane Wade did not respond to CNBC Make It's requests for comment.)

Nevada , United States - 26 August 2017; Conor McGregor, right, and Floyd Mayweather Jr during their super welterweight boxing match at T-Mobile Arena in Las Vegas, USA.
Stephen McCarthy | Sportsfile | Getty Images

Rivero estimates that he's made shoes for 1,200 athletes in the NFL, between 150 and 200 in MLB, 50 in the NBA and almost half of the UFC. This season, he's partnered with New Orleans Saints quarterback Drew Brees to create a pair of custom cleats for each game to raise money for different charities.

"Marcus Rivero and I have been friends for a long time. I've always admired his work," Brees tells CNBC Make It. "With his help we've been able to bring this project to life with unique cleat designs throughout the season." (Brees and Rivero first met two years ago over a project they collaborated on called My Cause, My Cleats.)

Rivero's custom cleats are so popular with NFL players that they're willing to risk significant fines to flaunt them. The 2019 NFL Rulebook states that players can wear shoes that are black, white or team colors, and styles must be pre-approved by the league.

Rivero's cleats often break NFL rules, and sponsors don't necessarily love them either. In 2014, Nike sent a pamphlet to its athletes threatening to end endorsement contracts of anyone who wore customized sneakers that covered up the company's iconic Swoosh.

Photo courtesy of @SolesBySir

But the rules haven't kept some league superstars from sporting designs from Soles By Sir and other designers in the space. In a 2016 game against the Detroit Lions, Odell Beckham, Jr., then a wide receiver for the New York Giants, paid a $18,231 fine for wearing cleats designed in honor of late NBA analyst Craig Sager. Seattle Seahawks running back Marshawn Lynch was nearly ejected from the 2015 NFC Championship Game for sporting a pair of $2,500 custom cleats by Rivero that included 24K gold paint flakes and a factory-made chrome plate bottom.

GLENDALE, AZ - FEBRUARY 01: Marshawn Lynch #24 of the Seattle Seahawks stretches prior to Super Bowl XLIX against the New England Patriots at University of Phoenix Stadium on February 1, 2015 in Glendale, Arizona.
Rob Carr | Getty Images Sport | Getty Images

Customizing other people's prized possessions is something of a family business for Rivero.

In high school, he worked for his father's auto-repair business, outfitting customers' cars with fancy rims and wheels in a style Rivero describes as similar to the vehicles featured on the MTV show "Pimp My Ride." Rivero would put in a few hours after school and on the weekends, but felt he wasn't making enough money.

"I started dating, and you know how that works," he says. He began making at home "a glorified Cuban long bread," a traditional sandwich stuffed with ham, cheese and mayo, to which he added a secret ingredient, honey mustard. He would divide the 10-inch sandwich into three pieces and sell them around school each for $2. Eventually he had 15 employees – including two teachers and a janitor who helped sell the sandwiches from their own backpacks – and was earning about $1,500 a week, while still in high school.

Encouraged by his early success as an entrepreneur, Rivero launched an internet company with his parents during his junior year of high school, selling the old wheels and tires customers from his father's shop left behind.

Marcus Rivero of Soles By Sir on the right and his father on the left.
Photo courtesy of @SolesBySir

After high school he enrolled at Case Western Reserve University, where he played defensive end and linebacker on the football team. But he found that the company was taking up a lot of his weeknights and making it hard to find time to study. He transferred to University of Miami, and at age 25 he sold the internet company to a competitor.

After college, Rivero founded TM Tires, a used tire wholesaler where he still works 9 to 5 on most days. "It's what gave me the freedom to paint," he says. He fulfills orders for Soles By Sir from a studio at his tire company after work until midnight, sometimes working until early in the morning, depending on the time of year.

Photo courtesy of @SolesBySir

Rivero had never really painted before he made his first custom shoes seven years ago.

"I wanted to get somebody something really cool for Valentine's Day, and I've always been a sneaker guy," Rivero says. "This girl I was dating wasn't really a sneaker person. I figured, what the heck, let me try getting her sneakers, but I couldn't find them in a cool color."

He bought paint and brushes and spent 20 hours transforming a black and grey pair of Nike SB Dunks into something glamorous, dusted with glitter. She loved them, and so did all his family and friends who saw her Instagram post and requested a pair of their own.

"Next thing you know, friends and family were like, 'Oh, I didn't know you could paint.'" Rivero says he remembers charging $100 to $150 per pair, but it was still taking him 15 to 20 hours to make each set. It was an Instagram shoe photo posted by one of Rivero's family members that caught Carroll's attention. He eventually asked Rivero to design 12 custom pairs of black Jordan cleats.

Carroll had Rivero ship the cleats to the Dolphins training facility. He opened them in front of his teammates, and everyone wanted to buy a pair. Carroll sold 10 pairs for a total of about $6,000. He sent the money to Rivero, and word began to spread.

Photo courtesy of @SolesBySir

"Better than him having made that much money that day was the fact that he gave my number to eight different Dolphin players," says Rivero. "That night I had eight different clients and literally through Instagram, through social posting, through, 'Hey, that was my college roommate but I play for the Seahawks,' 'Hey, I just played there and I got picked up by the Browns,' – that is how it all started."

It hasn't stopped. Rivero says most athletes he works with get in touch with him through Direct Message on Instagram. Shoe designs are often brainstormed through a five-minute Skype or FaceTime call with them. That's Rivero's favorite part of the process.

"You'd think that the wild ones have a wild personality and a wild fashion sense, and you'd think that the quieter ones don't. It's completely the opposite, so it avoids me going wild on somebody who I think is a wild type of guy or going mellow on somebody who really wanted polka dots."

Photo courtesy of @SolesBySir

"Everybody on my phone is saved under 'Sneakers,' then the name, then the team," he says. "My 'Sneakers' part of my phone is thousands of athletes. I always joke that if I lose my phone, somebody is going to have a field day." Rivero says his roster of celebrities includes Drake, Lil Wayne, Blake Shelton, Nick Cannon and Ellen DeGeneres. (Representatives for each did not respond to CNBC Make It's requests for comment.)

Photo courtesy of @SolesBySir

Riley Jones, news editor at Complex Network's sneaker-focused Sole Collector, tells CNBC Make It that the trend of athletes customizing their game shoes has been blowing up more and more over the past few years – so much so that the NFL has begun to show a little more leniency toward players' uniform rules, and other professional leagues, like MLB, are following suit.

Photo courtesy of @SolesBySir

"There was one period in 2017 where players were facing, just from the league, a lot of fines, a lot of backlash over what they were wearing," Jones says. "And then as players resisted and fans resisted, the league kind of backed off, they started allowing a little more freedom with the cleats."

In 2016, the NFL launched an initiative called My Cause, My Cleats, which gives players a dedicated week of the season to wear any personalized pair of custom cleats that support their favorite charitable organizations. After their games, the cleats can be auctioned off through the NFL Auction, with proceeds going to the player's charity of choice. Over the past three years, nearly $600,000 has been raised through just the NFL Auction alone, a spokesperson for the NFL tells CNBC Make It. Last year, more than 800 athletes participated.

Many players work directly with Nike, Under Armour and Adidas to design their cleats for this special week, but other teams outsource theirs to independent designers like Rivero.

Photo courtesy of @SolesBySir

This year, the My Cause, My Cleats initiative kicks off on Dec. 5, and Rivero will design cleats for entire teams, anywhere from 20 to 50 players on teams including the Miami Dolphins, Tampa Bay Buccaneers, Indianapolis Colts, Cleveland Browns, Washington Redskins, Jacksonville Jaguars, Houston Texans and Oakland Raiders.

It takes Rivero anywhere from three to 12 hours to design one pair of cleats, so managing his time is key. He'll design cleats for 250 to 300 NFL players in total. "We're working on it two and a half months beforehand," he says. One of his first big clients for the campaign was Brees.

Photo courtesy of @SolesBySir

"You work 24 hours sometimes," he says. "It's just — you gotta get it done, it is what it is."

Outside of the My Cause, My Cleats initiative, NFL players still can't sport custom cleats whenever they want, which Jones says might actually further fuel their popularity. In the fall season alone, Rivero is customizing an average 600 to 700 pairs just for the NFL.

"You have players who will just completely resist [the guidelines] and wear them anyway and take the fine," Jones says. "Because they would rather express themselves and do their own thing as opposed to worrying about a fine." A workaround for athletes who want to show off their custom cleats has been wearing them during pregame and warm-ups.

That's the spirit that Rivero, whose motto is "one of one," wants to empower. It's an attitude he developed early, in his father's auto shop.

Photo courtesy of @SolesBySir

"Every time somebody has a pair of shoes on, there's no duplicate, there's only 'one of one' of that shoe," he says. "That's been my model since day one. These athletes, they can buy whatever they want, so I always tell people if they can just envision a parking lot full of Ferraris, they can all buy them, but what's going to make one Ferrari better than the other? Let's just do a custom paint job on it. That's typically what I do – you always have the original on your foot."

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