This story is part of CNBC Make It's One-Minute Money Hacks series, which provides easy, straightforward tips and tricks to help you understand your finances and take control of your money.
Side hustles can be a great way to bring in some extra cash, but starting one can be challenging.
Jennifer Shealey knows that well. For years, she had to work two part-time jobs to stay afloat, in addition to her digital marketing side hustle on Fiverr. But sticking with it paid off, and eventually, "I was basically making more with Fiverr than I was with those two jobs together," Shealey previously told CNBC Make It.
Since starting on the freelancer platform in 2014, Shealey has made over $366,000 in sales.
Along the way, Shealey learned a few valuable lessons about how to build a business. Here are four tips to start a successful side hustle while having a full-time job, according to Shealey and others who have turned their side hustles into businesses making six figures or more.
First, think of something that you're passionate about and have a knack for.
Prior to starting her side hustle in 2014, Shealey had a job that she wasn't excited about. But it showed her how important it is to "stay true to your passion and your goals," she previously said.
And once you've found your passion, Shealey recommends to "just start." Don't overthink things.
"I think that's what gets people tripped up, especially because we're constantly on social media and we're looking for this perfection and you don't need perfection," she said. "You just need heart and a vision."
Next, research different freelancer platforms, like Fiverr or Upwork, which can help you find clients and build up your brand.
"You don't have to know anybody," Shealey said. "I didn't know anybody. I just logged in and I created a username."
Although he had a network of customers from his career as a teacher, Lambert still turned to a freelancer platform because "as you work on your own, you realize how difficult it is to build a business," he previously told CNBC Make It.
"Even though I had it good, I realized that [focusing on] these other pieces — like driving traffic, advertising and public relations — was taking my time away from what I really like to do, which is to write the resumes, to get people results and get them hired."
Third, set a work schedule and stick to it.
This can be difficult with a full-time job, but establishing times to work on your side hustle can help develop a routine.
Shealey used "all the extra free time that I had," she said. That included in the evenings after work and on weekends. "I sacrificed so that I didn't go to parties, and I said no to a lot of things, because I was really wanting to focus on Fiverr."
In staying diligent and consistently working on their side hustles, especially at first, both Shealey and Lambert were able to grow their customer bases, and ultimately, bring in more revenue.
And last, be flexible with your prices. As your business grows, you can raise prices accordingly.
When she first started offering marketing services on Fiverr, Shealey would design Facebook advertisements for her customers for as low as $5.
"Some people might find that silly starting out, like, 'Why would you do that?' Well, sometimes you have to do what you got to do to put your name out there," she said.
Over time, she progressively increased her pricing. Now, her work costs anywhere from $20 to $125, depending on the type of advertisement and how much work it takes, among other things.
Nonetheless, it's important to stay patient, as it may take time to achieve success.
"I just wouldn't give up. I didn't see a huge return in the first three years, and I was busy working other part-time jobs," she said. "But, I just wouldn't lose heart."
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