Ever thought about starting a business? The Story Exchange talked to Becky O'Neil about how she turned a passion for pets into a major business in this 2012 video. (Video credit: Sue Williams)

You wouldn’t think soft-spoken Becky O’Neil runs something of a pet-care empire in Northern Virginia. Some 21 years ago, the former X-ray technician began walking pets with her young son strapped to her back. Today, she employs more than 170 people, serves 5,300 active clients and projects a healthy chunk of revenue — $3.6 million this year alone. “Maybe a little more,” she says.

Her nonchalant demeanor belies her astute business sense. When we first spoke with O’Neil back in 2012 (watch video above), she told us how she quickly grew her business, Becky’s Pet Care, by word of mouth. O’Neil also credits the company’s rise to good timing — pet sitting was just starting to take off — and customer service. Over the years, Becky’s Pet Care has been cited by Angie’s List, Washingtonian and Pet Age magazines; it has been named “business of the year” by the National Association of Professional Pet Sitters, a nonprofit trade group.

[Related: Read how Becky O’Neil started Becky’s Pet Care]

But before she had even walked her first dog, O’Neil says she had thoroughly researched the market and written a business plan. “An idea is great, but you need more than just an idea,” she says. “You need to know how you’re gonna make the idea come to life.”

In the spirit of National Small Business Month, we recently checked in with O’Neil to get her best advice for starting and running a business. She told us these three things:

1. Stay ahead of the curve.

O’Neil says she’s a big believer in “constant evolution” or continual improvement. “We’re always trying to do the next best thing,” she says. “I research, read, go to events, network with other pet care professionals, and really try to keep on top of everything that’s going on in the industry so that I can be a front runner.”

A good example of how her business has changed over the years is her investment in tech. Cloud-based software and smartphone apps have replaced desktop programs and index cards. When O’Neil first launched Becky’s Pet Care, she and other sitters would leave a written report card for clients, with details of how the pet did that day. Today, clients still get a report card, but “it’s not left on the counter anymore,” she says. “They get it in an email with photos attached, and so they have it instantly, and with pictures of their furry friend.” Not to mention, “it’s time and date-stamped, location-stamped, so it’s a little more accountability,” she says.

[Related: Check out more Advice & Tips for women entrepreneurs]

2. Think of competitors as collaborators.

This might not be the same in every industry, but at least in pet-sitting, “most of us really don’t call each other competition, but colleagues,” O’Neil says. “The pets come first.”

When she started in the late 1990s, pet-sitting was still in its infancy, “and so when you’re in a new industry … you really need to work together with your peers and collaborate.” That means she will refer some potential clients and even job candidates over to her “competitors” and vice versa. “Everybody isn’t the right fit, and we’re just a very connected group of business owners [who] happen to be in the same industry,” she says.

3. Be conservative when it comes to cash.

O’Neil is a big believer in budgeting. “Margins in the pet care industry are pretty small,” she says Becky’s Pet Care has three locations, including a new office and training facility in Springfield, Virginia. One of her company’s biggest expenses is customer service — specifically, having staff available to take calls and answer clients’ questions, 9 a.m. to 7 p.m. on weekdays and even some weekend times.  “All that is money, but that’s how I want to run the business,” she says. And every year, she updates her business plan to strategize for growth, such as new areas or territories she wants to expand into — but “it costs money to grow,” she says.

In the past, O’Neil says she’s made the mistake of spending money before it’s in the bank. “When you look at the cash flow and it’s going in the wrong direction — more money is going out than is coming in — it’s alarming,” she says. While she has a line of credit, she is loathe to tap it. “it would be much better if you just didn’t spend it.”

One last thing O’Neil has done over the years to grow her business: She’s accepted more types of “pets.” While she started out walking dogs, she’s expanded to cats, iguanas, fish, rabbits — and more recently, chickens. Once considered lowly farm animals, “chickens are becoming family pets, and they provide the benefit of fresh eggs, so people are liking their chickens,” she says with a laugh. Keeping up with trends “ keeps you fresh and relevant,” she says.  “It keeps it exciting.”

[Related: Learn about more business ideas for women entrepreneurs]