Four successful entrepreneurs share the same advice for achieving success: Begin now.

It's possible to build a successful business from scratch, although it may not be easy.

I've conversed with various entrepreneurs while working at CNBC, including those who built thriving side hustles and the founders of multinational unicorn corporations. In my experience, success ultimately boils down to one's beliefs.

These individuals decided to trust in their own abilities, even though they recognized the challenges ahead. Despite the difficulties, they believed in the possibility of achieving their goals. As a result, they were willing to take significant risks and make sacrifices in pursuit of their dreams.

Often, people viewed as inspirational are simply ordinary individuals who have experienced challenges and learned valuable life lessons.

I've discovered that successful entrepreneurs often provide the same advice in my conversations with them.

Here's what they credit for their success:

Advice #1: Anyone can do it

Despite not being a professional baker, Jason McGowan successfully co-founded Crumbl Cookies in 2017 and built a thriving cookie business.

Crumbl, a unicorn company, has over 1,000 locations worldwide and generated over $1 billion in sales in 2022, according to CNBC Make It documents.

"McGowan stated to CNBC Make It that he never thought in his wildest dreams that they would achieve over $1 billion in sales. As he grows older and builds the company, he realizes that everything they do can be done by anyone."

McGowan and his co-founder had never been in a professional baking kitchen before, but they often experimented with chocolate-chip cookie recipes during their free time. Now, their cookies are popular worldwide, and it was all due to their belief in an idea and trying it out.

Anne Mahlum echoes the same sentiment.

In 2013, she established a New York-based boutique fitness chain, Solidcore, which now has more than 100 locations after a decade.

In 2023, Mahlum became a multi-millionaire after cashing out on her equity in the business and earning $88.4 million.

"Through Solidcore, I've learned that you can achieve anything you desire, as long as you're willing to put in the effort," Mahlum shared with CNBC Make It.

Advice #2: Lean into what makes you unique

Mahlum advised leaning into one's individuality as a key to success.

"Embracing our uniqueness is key to achieving success. By leaning into our individuality, we can harness its power to our advantage. This has been a significant factor in my personal and professional growth."

She stated, "We often believe that entrepreneurs and successful individuals possess something unique or have distinct advantages. While it's true that life and the world are not always fair, this has always been the case and will continue to be so."

Mahlum stated that everyone possesses a unique set of circumstances, including advantages and disadvantages.

"It is our responsibility to determine our advantages, talents, and skills and utilize them to achieve success."

According to McGowan and Mahlum, those who have "made it" are not special; they simply emphasized their unique qualities.

Edward Tirtanata, CEO of Kopi Kenangan, emphasized what distinguished him from others.

He advised fellow entrepreneurs to stand out, according to CNBC.

In order to compete against incumbents, you need to be radically different, as the next Starbucks, McDonald's, and Google will not resemble their predecessors.

In 2017, Tirtanata established a local Indonesian coffee stall, which has since expanded into an international coffee brand with over 800 locations in Southeast Asia, generating more than $100 million in annual sales, as per CNBC Make It's documents.

Advice #3: Be passionate

Shawn Tsao loved sandwiches – a burning passion, some might say.

In 2012, he yearned for a sandwich from a particular store located far away, but he lacked the time to travel there.

The idea for food-delivery service Caviar was born when he wondered, "What if there were an Uber for food?"

In 2014, Jack Dorsey's payments company Square (now known as Block) acquired Caviar for more than $100 million. Tsao and his co-founders earned millions from the transaction.

According to Tsao, being an entrepreneur and genuinely passionate about the product you're building, rather than just seeking the accolades of being a CEO or founder, will help you endure the toughest days.

Tsao founded Caviar to meet his own needs, and his personal passion sustained him through the challenges he encountered while building the business.

Tirtanata, Mahlum, and McGowan all built something for themselves, with Tirtanata loving coffee, Mahlum caring about fitness, and McGowan being passionate about cookies.

They persevered through tough times due to their genuine passion.

Advice #4: Just get started

The most common advice I've received from entrepreneurs in my conversations is to just start.

Mahlum said, "I have a phrase that says: 'Just have a day one,' and Nike got it best with their slogan, 'Just do it.'"

One day, Mahlum stumbled into a Pilates studio in Los Angeles and fell in love with it. Months later, she invested all her savings into opening her first studio. That was day one for her.

Despite not knowing how to bake cookies, McGowan still started a successful cookie company.

Starting a business requires taking action, even if you don't have everything ready. You just need to begin and make progress.

He emphasized the significance of taking early action, stating, 'Just to move is what's really important to success'

These four founders amassed their fortunes by having faith in themselves, seizing opportunities, and starting from scratch.

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