If your hand is firmly raised, then listen up: The fantasy—which you’d be forgiven for thinking is restricted to those in Silicon Valley or movies—is not entirely unrealistic.

London-based Steph Douglas did exactly that when in 2014 she left her job as a branding marketer for EDF Energy to devote herself full-time to her online gifting company Don’t Buy Her Flowers. 

Douglas came up with the idea for the business in 2010 when, after having her first baby, she received more bunches of flowers than she had vases for and noted that new mums really didn’t need another thing to take care of in addition to a newborn.

For the next four years, while juggling childcare and advertising campaigns (and having a second baby), Douglas built her brainchild in her spare room after her normal workday ended.

It’s an all-too-familiar balancing act. Research consistently shows that people are increasingly turning to side hustles to earn some extra money as the cost of living rises.

For Douglas, the struggle of putting in extra hours of work into her passion project paid off. Last year, the business turned over £2.5 million ($3 million). Here, she gives Fortune her top five tips for going from a part-time wannabe founder in her spare room to earning millions. 

Don’t quit your day job

You’ve got your idea. You’ve done the market research, which has come back with positive results. You’re raring to go—and all you want to do is pack in your day job, to give your side hustle all your energy. 

Don’t jump ship too soon, Douglas warns.

Even though it may feel as if you need to give your business venture all your focus while the ball is rolling, there really is no rush to success, and most overnight successes were years, if not decades, in the making. 

Douglas says that having the security blanket of a salary is “not a bad thing to do whilst you’re getting really clear [on your idea], because it could well be that the first side hustle you try isn’t quite the right thing or doesn’t quite land the way that you wanted to land.”

Use that time to really home in on your craft, so that you know it will take off when you do eventually hand in your resignation letter. 

“Know exactly what it is you’re trying to sell so that you can be really clear with your messaging and know that you’re really filling a gap that you’ve identified,” she adds.

Lean on your network

It’s often easier to toot your own horn to strangers than to those closest to you, but Douglas advises founders to not be afraid of using their connections. 

“Whether that’s people at the school gate, your friends, or your family, get them involved, get them excited,” she says, while adding that it’s a free way of generating buzz around your brand when you’ve got zero budget. 

Tapping into your network isn’t useful only when you’re gauging interest in a concept. Douglas has also brought friends and family into her team as her business has scaled.

Her brother is the director of operations, and both her head of customer service and warehouse manager are old school friends. 

“Quite often the message is about not mixing business and pleasure. But actually, you’ll have an instinct[ual] trust if you know that they’re the right person to do that job,” Douglas says. 

Although taking a step back and letting other people manage various aspects of your startup can be difficult as a new founder, it’s a vital step in scaling up—and Douglas maintains this is easier to do with the people you love than strangers. 

“They’re kind of in the business with me—they’re really part of it. You have that loyalty of people who really want it to work alongside you. It would be quite hard to hire for that at the beginning,” she adds. 

DIY—where you can

“To keep your costs as low as you can, do as much as you can yourself,” Douglas advises.

In the first few years of running her side hustle, she was her own social media manager, PR, and fulfillment team. “That was obviously quite stressful at times. I had two small kids and was always at work because there were always orders to pack. But it allowed me to really test the concept without having to spend money on a warehouse space or people.” 

Similarly, no one knows your product or service as well as you do. It’s why it’s probably better to run your own social media accounts until you have nailed your brand’s tone of voice and the way it should look on people’s feeds, and have built a small community of followers. 

As well as saving you money, this will enable you to learn more about what resonates with your customers before outsourcing a marketing team.

“If someone’s going to at some point do it for you, you need to understand what it is they’ll be doing. There are agencies that can do everything for you. But unless you know exactly how it works, you could well be paying over the odds,” Douglas adds. 

Take a leap of faith

That being said, there is a limit to how much you can do yourself without strangling the business. Looking back, there were times when Douglas believes that being too cautious with outsourcing costs “held her business back.”

When every penny counts and your main goal is for your side hustle to make money so that you can turn it into your full-time gig, it’s an easy mistake to make.

But actually, it might pay off to think about the bigger picture and where your energy is best utilized.

If Douglas stopped fulfilling orders herself sooner, she says, that she would have had more time to focus on the business’s PR, and it may have scaled quicker.

She assures others that despite often thinking “we can’t afford that person yet, or we can’t afford to move out of the house [office to a warehouse], each time we did take that leap, the business would grow.”

A side hustle to her side hustle

And if things aren’t working out, you can always launch a secondary side hustle to supplement your main side hustle. 

Don’t Buy Her Flowers experienced a surge in sales during the pandemic, when shops were shut and people could only purchase gifts online. 

“This huge boom actually meant that the team and our warehouse had to get really slick,” Douglas says. The sensitive nature of her business—in which one gift could be for new mothers, and another could be for someone who has just miscarried their child—means that the team has to fulfill orders at pace with extreme accuracy and caution. 

Now, with consumer confidence dwindling, the business has been receiving fewer orders. It’s in contrast to the potential number of orders that Douglas’s team could fulfill. 

So she’s putting her warehouse to good use by offering a new service: packaging other startups’ orders. And the efficient use of her space and team has become an additional revenue stream—or if you will, a side hustle to her side hustle.

“We don’t have the same costs tied up in it because I don’t own the stock. So we’re obviously housing the stock, which we charge the storage for. And then we’re fulfilling the stock, which we charge for. But the risk is much smaller,” she adds.