Jessica Alba

The actress and SELF contributing editor started The Honest Company, which produces non-toxic family and home products, in 2011.

My Mantra "At every point in your career, you have to have hustle. Each milestone presents new challenges."

What I've Learned "I have mixed feelings about [going into business with friends]. I've hired some friends and family. It hasn't always gone well, but when it does, they're people you can confide in, in a unique way."

How I Stay Balanced "One day's so different from the next. If I get in four workouts a week, I'm like, 'I did it!'"

Courtesy of Under Armour

Adrienne Lofton

The seasoned brand strategist has ascended through the retail industry to land the role of senior vice president of global brand marketing at Under Armour.

My Mantra "Stay true to who you are and what you believe in. I know that if I show up each and every day at work as my true self, I won't have to sacrifice my personal beliefs and that's led to the kind of integrity and productivity I can be proud of."

How I Get It Done "I have never found success by working in a silo. Through every stage of my career, it's always been about team work, even as I've transitioned from contributor to leader. In my role now, I am responsible for delivering the vision, direction and guidance, but we as a team drive our brand to the next level. I wholeheartedly stand behind the decisions my team makes every step of the way."

My Advice "Try not to let yourself live with regrets. In taking chances and making mistakes, I've learned lessons that have helped me develop professionally and emboldened me to become who I am."

Courtesy of Liz Gateley

Liz Gateley

She left a career in law to pursue her passion: entertainment. After developing shows like Laguna Beach and The Hills at MTV, Gateley now oversees Lifetime's movies and series as executive vice president and head of programming.

What I Learned "Don't be afraid to take a step back to take a huge step forward. Years ago, I went from being a lawyer to being the happiest mail-cart pusher at a talent agency, because I was on the path I wanted to be on."

My Advice "Bring your boss solutions, not problems. I instill this in all the people under me that I work with. And be nice to assistants because they control everything. The assistant today is going to be the executive tomorrow."

How I Get Perspective "We all have those moments when we wake up in the morning—believe me, I have them once or twice a week—when you're like, 'I don't know if I can do today!' It's so relieving to say, 'Forget it! I've been around this merry-go-round enough times to know I'm going to be fine. The world will not end.'"

Sahar Wabeh

Yoko Shimada

When she became a mom and saw a major need for post-baby clothing, Shimada left her career in public health to found Mitera, a professional clothing line that makes breast-feeding and pumping easy for new working moms.

How I Get Inspired "Make your friends into your market testers for new ideas. Talking to other working moms helped me see a hole in the market, which made me decide to build Mitera and empower women like myself, who want to do it all."

What I Learned "You're more prepared than you think. When I started Mitera, every day I thought, 'I've never done this before, I don't know what I'm doing.' But people reminded me, 'You can relate to people, you've worked with high-level executives—you can apply that to networking with people in this new industry.' You might be doing something different, but you have skills that you can use in your new role."

How I Get Perspective "It's really important to have a support system. Not just for advice, but to be open with and share what you're going through. Every day I'm fighting my fears and doubts and wondering if this is worth it, and talking with other women helps me realize we all have these issues. It gives you more confidence and helps you realize you are doing the right thing."

Keith Morrison

Danielle Weisberg and Carly Zakin

The two former producers for NBC News partnered up to launch theSkimm, an email-based news delivery service.

Our Advice "People say, 'Be open to everything.' We follow a different trend: Say no—a lot!" says Weisberg. "It's how you focus and reach important milestones when you don't have a lot of resources," adds Zakin.

How We Made It Happen "Don't take no for an answer. There's obviously a fine line between being annoying and showing you can hustle and it's important to know that line. But we got turned down over and over again. Whether it was meeting with people who had been inspiring to us or fundraising for the first time, we heard no again and again. That's something you have to respect, but you need to know if you're a person who says 'Ok, I tried and it didn't work' or if you're going to do it no matter what," says Weisberg.

What We Look For In Employees "We hear all the time from people who want to go straight to a startup, but we both think it's really important to first have experience from a larger environment. That's where you learn how to be a professional," says Weisberg. "The foundation of our company is that we are a news organization, [which involves] journalistic integrity and ethics. That's not something you can wing."

Courtesy of Christina Sass

Christina Sass

Cofounder of Andela, an African-based employment training program that helps companies seeking tech experts find skilled developers.

My Mantra "Timing is never perfect; be ready to act! I walked away from a doctorate program to start Andela, because when my cofounders and I came up with the idea, I knew it was what I had to do."

What Sets Us Apart "We outcompete through diversity. At Andela, we set out with a goal of having 35 percent female software developers, which is an audacious goal. And it's part of the value proposition that we offer to our clients. Usually you have a team of largely male, white developers who come from a similar background. But our people are experts in emerging markets and they're going to approach problems in different ways. They're going to consistently look to problem-solve and add value from a different perspective."

My Advice "Fiercely protect the culture of the company you want to build. You can write down what your company's ethos is but unless you live it, unless you really protect it every day that will not be it. Culture is in the air—it's the unwritten rules. As the leader of the organization, if you don't stop and pick up that trash, no one is going to. If you don't take the time to say something respectfully even when it's hard, no one else is going to. You have to be the protector of the real culture that you think is necessary to help your company succeed."

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Sana Amanat

The director of content and character development at Marvel is working to create a more diverse range of comic-book superheroes.

How I Stay Balanced "Find the little details of your job that give you joy—they get you through hard days. Personally, I love figuring out the look of a new character or even picking the perfect font for a story."

How I Get Inspired "At one point I was struggling with whether I should stay in comics and I wasn't creating anything that I felt connected to. It was actually my brother who said 'You have an opportunity with this company—you have a huge platform you can use to talk about things that you're passionate about. Don't underestimate that. It's a really great brand and a huge entertainment company; use that to share things that you're excited about through the stories you tell.' And I really connected with that. That was way before Ms. Marvel (a new Pakistani American and Muslim character) happened, and then suddenly I was thrust into the position to do just that with her."

What I Learned "When I started working in comics, I had a lot of uncertainty about whether I was good at this, whether I belonged. But then our chief creative officer told me, 'The reason we want you here is because of the unique creative voice we know you can bring. It's fine that you didn't grow up reading comics; you know great stories. And because you come from a different perspective, you're going to allow Marvel to evolve in a way that we never thought could be possible.' And I think that's the case for any industry—really unique voices are going to create opportunities to tell even better stories."

Courtesy of Sophia Amoruso

Sofia Amoruso

At 22, Amoruso started at eBay store selling vintage clothing, which led to the founding of her own line, Nasty Gal. She's the author of #Girlboss and the new book Nasty Galaxy.

My Mantra "Don't compare your hustle to someone else's highlight reel. People probably look at me and think that my life is perfect, but that's because I'm not posting about my bummer day on social media. It's easy to look at other people and think that you're not doing enough."

What I Look For In Employees "The ability to make order out of chaos. And, for me, managing up. It's so helpful when people are like, 'This is what I need form you' and learn how to use me in ways that actually get things done for them. That's really an art."

My Advice "Probably the biggest mistake female entrepreneurs make is thinking they're different from male entrepreneurs. The playing field is not level, but if you show up at the table like a peer—and this is only in my experience—people will treat you like one. And if they don't, then you prove that you know what you're talking about. Success is the greatest negotiating power."

*This article originally appeared in the October 2016 issue of SELF. *