In 2011, when I wasn't working my $25,000-per-year insurance job or spending time with my family, you could find me shopping online.

I was 24 years old, and I loved browsing the internet for clothes that were both on-trend and affordable. Unfortunately, there weren't too many options back then. That's what gave me the idea to start a side hustle selling women's clothing on eBay.

At first, it was just a fun hobby. Little did I know, 10 years later, my husband Chris and I would be running Pink Lily full-time. Last year, our online clothing business generated $141 million in gross sales. And today, our social media audience has grown to 3.6 million followers.

From an eBay side hustle to $141 million in sales

To start our eBay store, my husband Chris and I made an initial investment of about $300 to buy clothes and accessories from a wholesale website.

Since I wasn't familiar with pricing strategies, I priced items at what I would pay as a customer. We worked out of our living room, so we didn't have much overhead to worry about except for shipping costs.

Profits varied during the first few years, but we typically made anywhere from $300 to $1,000 per month. We used that money to pay off student loans and invest back into the business.

I'd fly to Los Angeles to meet with vendors and place product orders, and eventually started attending trade shows to expand our line of selections.

Two years later, in 2013, I started a personal Facebook group to market my clothes. We had loyal customers who showed an increasing demand for our products, especially in our local community in Bowling Green, Kentucky.

By the end of the year, we had saved around $20,000 from our profits, which we used to launch Pink Lily's official website. That's when business really began booming.

In May 2014, we surpassed $100,000 in monthly revenue. After three years of running Pink Lily as a side hustle, I quit my insurance job to work on the business full-time. Chris joined me a few months later to oversee the company's finances and operations. We closed the year with more than $4 million in revenue.

In 2019, after achieving $70 million in total sales, we received a minority stake investment to support the business' rapid growth. This helped us expand our product offerings and scale an amazing team.

Currently, we sell more than 11,000 products on our site every day, have a brick-and-mortar store and, with 250 full-time employees, are one of the biggest employers in Bowling Green.

While we still visit trade shows, we now have a core group of vendor partners who we work with to create custom designs.

Co-founding Pink Lily alongside my husband has been the journey of a lifetime. Here are my best tips for starting a successful business:

1. Find a gap in the market

You've probably heard some version of this before, but I can't kick off entrepreneurial advice without hammering this point home: It's so important to find a gap in the existing market.

When I started my side hustle, I saw an unmet need for fashion-inclined women who wanted to be able to find a dress for $50 or less. I knew I could help to fill that need in my own small way.

2. Reinvest your profits

If you want growth to happen quickly, you need to reinvest all or most of your early profits back into the business.

You may be very strapped for cash during the first few years. That was our experience, and it wasn't easy. We worked up to 60 hours per week, lived frugally, and reinvested the money we made back into growing Pink Lilly.

3. Find fun, unique ways to engage your social media followers

Being active on social media has been a key part of our success. We regularly ask our 1.4 million Instagram followers what they'd like to see on our site and on our shelves.

For example, we'll post photos of items we are considering purchasing or brands we could partner with for Pink Lily. Then we'll use everyone's responses and feedback to make any final decisions. This helps shoppers feel like insiders and part of the family.

We also ship products in custom bags printed with our company logo and the hashtag #pinklilystyle. Then we'll feature customers who post a photo of themselves in their new outfit on Instagram, along with the hashtag, on our website.

4. Empower loyal customers to be brand ambassadors

I always encourage entrepreneurs to carefully consider how they can design a brand ambassador program that resonates with their customers.

At Pink Lily, our program offers paid positions — with a 10% commission offered on every sale — to an exclusive group of longtime customers who can authentically vouch for the products. This is an important, sustainable part of our marketing strategy, and generated about $7.5 million in sales last year.

5. Find something you can truly own

It's essential to carve out a niche or a product line that you can exclusively own as a company. What will come to mind when consumers hear the name of your brand?

We'll often buy out a vendor's entire inventory when we find a special product, for example, so that no other retailer can access it. This way, we end up with curated collections that can only be found at Pink Lily.

Tori Gerbig co-founded Pink Lily, an online women's fashion store, as an eBay shop in 2011. Today, it one of the fastest-growing online retailers in America. A graduate of Western Kentucky University, Tori resides in her hometown of Bowling Green, Kentucky with her husband and co-founder Chris, and their three children. Follow Pink Lily on Instagram and Facebook.

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