When Tim Brown retired from professional soccer, he found himself searching for his next meaningful endeavor. 

During his playing days, Brown says, he had enjoyed the free gear that brands sent to professional athletes, but he also wondered about ways to produce it without synthetic materials. He'd go on to co-found Allbirds, a San Francisco Bay Area sustainable footwear and apparel company. But not before reflecting on how purpose can fuel performance. 

Playing for his native New Zealand in the 2010 World Cup qualifiers, Brown says, "I saw the impact that I could have on my community and what it meant to my family." He spoke with Beatrice Dixon, co-founder, and CEO of the Honey Pot Company, an Atlanta-based feminine-hygiene company, at a recent Inc. streaming event.

Here are three practices Brown followed while going from goal-scorer to co-founder that other business owners and aspiring entrepreneurs can emulate.

1. Find your North Star.

Brown began making shoes as a side-hustle before he retired from soccer. He wasn't thinking of sustainability. But when he met engineer and renewables expert Joey Zwillinger, he began to understand the threat of climate change. The two founded Allbirds to create a sustainable alternative in the market. They launched Allbirds in 2015 as a B Corp, a social and environmental certification accountable for balancing profit and purpose.

They developed an alternative to petroleum-based ethylene-vinyl acetate, the rubber-like plastic used in shoe soles. Derived from the byproducts of sugarcane processing, the material is much kinder to the planet. They didn't stop there. "We were able to lower our cost by making [the material-making process] open source and do more good in the process," says Brown. "It speaks to the power of purpose as a driver of innovation and risk-taking and creativity."

What about the name of the company? "It's a nod to New Zealand. When people first came to New Zealand, there was nothing there but birds, no mammals," Brown says. "And also the idea to that when the birds are OK, their environment is OK. That's been our purpose and our mission from the beginning."

2. Build a strong team.

What makes a good team? Differences, Brown says. "The differences create strength and the ability to go further together than you can individually," he says.

Allbirds' recent partnership with Adidas on the Futurecraft Footprint shoe is an example of this approach. The ultralight running shoe has the lowest carbon footprint per pair that either brand has made. Acknowledging that teaming up with a competitor to make a product is unconventional, he says, "At this moment, this existential crisis around climate change, everything should be on the table." 

3. Show up.

Brown urges other entrepreneurs to focus on continuous improvement and to just show up, listen to feedback, and improve their businesses and themselves daily. 

"Over time, if you're prepared to stick with something, more often than not, you're going to get there, and that's the key," he says.