February 27, 2015 4 min read

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One billion dollars -- that’s how much had been paid to freelancers via the oDesk platform in 2013. And the company forecast that its online work market will be worth $5 billion by 2018.

When you consider statistics like this, the freelancing industry seems to be booming. Yet, many freelancers still find it difficult to convert their freelance hobbies into careers.

Wondering how you can you win a big enough piece of the pie? Explore these five ideas:

Related: Create Side-Hustle Income by Teaching What You Already Know

1. Define your strategy.

Consider these questions to define your freelance strategy: What makes you different? What skills do you possess that people will pay for?

If you have a marketing background, don't just label yourself a marketing professional. Drill down and list specific skills that make you especially valuable.

For example a few descriptive phrases I draw upon are "marketing strategy, planning and implementation expertise, SEO analysis and reporting, website conversion optimization, content curation and editorial management."

If nothing comes to mind, think about skills you have always wanted to develop. Spend time researching their market potential and then get to work watching every relevant YouTube video you can find.

2. Optimize your freelance profiles.

Think of oDesk and Elance as search engines specifically for companies seeking freelancers. Much like a business optimizes its presence on Google, put your best foot forward by completely building out your virtual resume. This way, your descriptions are more likely to show up in the search results.

For example, on an oDesk profile, spend time to build out these sections: Profile Overview, Skills, Portfolio, Employment History and Education.

Also, some freelancer sites let you take aptitude tests. Achieving high scores could make you more attractive to prospective clients. Just be sure to take relevant tests, based on your strategy.

Related: 5 Ways Fiverr Jump-Started My Life as an Entrepreneur

3. Ramp up your prospecting.

If you want to win clients, it's a numbers game. The more jobs (that fit your skills) that you apply for, the more likely you are to get interviews.

Be judicious when considering prospective clients. Look for clients who have spent at least $10,000 online and who are committed to identifying long-term relationships.

Sure, the process can seem overwhelming. Therefore develop a prospecting plan and stick to it. Even if freelancers are turned down 70 percent of the time, that would still means 30 percent of the time they might have a good shot.

4. Send personalized cover letters.

Impress potential clients with a personal touch. When applying for freelancing gigs online, be savvy. Customizing the interaction is important and shows that you're interested.

Begin by researching the company (if publicly visible on the posting) and think about its described needs. Address the cover letter to the hiring manager’s first name. Never write, "Dear hiring manager."

Keep your message brief, but personalized and discuss how you could add value to the firm. Include your email, phone number, Skype ID and three or four available interview times in the next 48 hours.

5. Be wary of $50 projects.

In the age of Fiverr, freelancers often undervalue their services by pursuing jobs barely worth their time. This can lead to frustration, burnout and their perpetual status as a "hobby" freelancer.

Sure, fixed-price projects can be a great way to win a few quick clients. Just be careful to not take too many low-paying jobs and end up in a race to the bottom.

Freelancing offers someone a ton of freedom if done correctly. You could try for a big slice of that billion-dollar pie.

Related: 7 Steps to Launch Your Freelancing Career Full-Time