If you have experience in the marketing world or want to start a business that allows you to think creatively and recommend solutions for a diverse array of clients, launching a marketing agency could be a great option. The global market for digital marketing and advertising alone is estimated to be $322.5 billion and is projected to grow to $640.2 billion by the end of 2027. And within this industry, you can capitalize on any number of subfields, including niche areas of expertise that don't have much competition and fast-growing areas with high potential for profitability.

Of course, starting a marketing agency from scratch isn't easy. To succeed you'll need to follow a few important principles and strategies.

Get experience (one way or another)

First, you'll want to gain experience. As a marketing agency CEO with virtually no marketing experience, you'd be hard-pressed to make insightful recommendations to your clients.

The most common path is to earn this experience for yourself. Start as a freelancer, providing small-scale marketing services to a limited number of clients. Or develop your abilities by working for an already established marketing agency.

Related: 10 Marketing Strategies to Fuel Your Business Growth

If you don't have much experience of your own and you want to get started sooner, you can leverage the experience of other professionals instead.

For example, you can:

• Partner up. If you have a mind for business but limited marketing experience, consider partnering with a bona fide marketing expert who has limited business know-how. Complementary partnerships often work well.

• Hire someone. You can also substitute your lack of experience with a roster of highly experienced employees. With the right team, your minimal experience is a nonissue.

• Work with investors. If you have at least some experience, you can lean on the help of investors to guide you through the earliest stages of agency development.

• Work with vendors. You can also work with vendors as the primary source of your recommendations. In this model your agency works more as a conduit than a direct source of marketing strategies or tactics.

Find a way to distinguish yourself

There are more than 40,000 advertising and related agencies in the United States. That's a lot of competition. To find clients and establish a reputation for your brand, you'll need a way to distinguish yourself.

Fortunately there are many options to do this. For example, you could focus on a specific type of client, based on their company size, industry or stage of growth. You could also focus on a specific area, appealing only to people in your city or state. Additionally, you could distinguish your brand by offering a unique voice or perspective on marketing in general.

Don't shy away from white labeling

One option for new agencies and inexperienced entrepreneurs is white labeling. Through white labeling you'll work with another agency, offering their services to your end clients as if they were your own. Depending on the nature of this relationship, you'll likely be able to devise strategies, execute tactics, and even produce reports through your partnered agency; and all these assets will be presented by your brand.

You'll pay upfront for these services, usually marking up the price slightly for your end client. Profit margins are reasonable, your client still gets a great price and you can rest assured that your clients are getting the best quality work.

Practice what you preach

As a marketing agency, it's important to practice what you preach. For example, let's say your agency formally recommends search engine optimization (SEO) to its clients. If your clients conduct a few basic searches for your agency's website and are unable to find it, this is a sign of your agency's incompetence, hypocrisy or both.

To make a good first impression and land more clients, you need to master all the strategies you're recommending.

Serve your first clients well

Your earliest clients are going to be some of the most important. This is your opportunity to prove what your agency can do, and oftentimes, early clients serve as a gateway to a potentially endless chain of referrals. Do whatever it takes to make these first clients happy, even if it means taking small losses or making additional sacrifices.

Related: Why I Spent Hours Conducting Research for My First Clients — All Before I Was Paid a Dime

Have a plan to scale

Marketing agency margins aren't amazing, especially if you're outsourcing most of your work. If you want to make money long-term, you'll need a plan to scale and attract more clients. There are many ways to do this, each with advantages and disadvantages. For example, you could dump more money into marketing and advertising, establish a referral program, or open up new locations in different cities.

Related: The 5 Stages Startups Must Go Through to Make that First $1 Million

Starting a marketing agency is tough, especially if you have little experience in the marketing industry. But with the right strategy and accommodation for these important points, your business has the potential to take off.