Freelance writing started as a side hustle that helped me earn extra money after my husband passed away. I was a full-time therapist and writing gave me the flexibility to work during evenings and weekends.

I wrote articles for a variety of websites. And the more I wrote, the better opportunities I gained. Within a few years, writing turned into a part-time job that allowed me to reduce my hours as a therapist.

I imagined writing would remain a small portion of my overall income. But, in 2013, I wrote an article that went viral. Millions of people read it in a matter of days.

A literary agent called and suggested I write a book. Within a month, I landed a publishing deal with HarperCollins, one of the biggest publishers in the world.

I knew nothing about the publishing world at the time. But, my experience taught me a lot. Here are three biggest lessons I learned from publishing my first book:

1. A writing schedule is a must.

I had about three months to write my first book. And while I wasn't always a fan of the tight deadline, I knew I had to stick to a schedule if I wanted to get the book done on time.

There were a million reasons not to write--writer's block, social media distractions, and fear that my book wouldn't turn out well. A writing schedule was key to getting the work done. It kept me on track, even on the days when I didn't feel like doing it.

Many people say, "I'd like to write a book someday." But since 'someday' never appears on the calendar, it's easy to push it off until later. If you plan to write a book, block off writing time in your calendar and create deadlines for yourself.

2. Writing is only one small part of the process.

Research was a huge part of writing a non-fiction book. Fortunately, as a college instructor, I had access to countless journals at the college library.

But, I also needed anecdotes and information that couldn't be searched via a keyword. Whether I was looking for a historical figure or an everyday person to illustrate a point, finding anecdotes was one of the toughest parts of writing the book.

And research was only part of the battle. Marketing the book was a tall order. Interviews, articles, and speaking engagements were crucial to sales.

3. An author's business plan is unique.

Many seasoned authors offered their advice about how to turn a book into a business. I heard things like, "You write a book to get speaking engagements," and, "You do speaking engagements to sell books." Similarly, one person would say, "Create an online course to market your book," while the next would say, "Use your book as a tool to sell your online course."

With so many different ideas about the "right way" to earn a living as an author, I realized that each author's business plan is unique. It's up to you to decide what information to give away for free and what products you want to sell and how you want to sell them.

Over the past few years, my business plan has shifted a few different times. As my career evolves, so do my revenue streams. And staying flexible has helped me capitalize on the avenues that work best for me.

How to Get Started

There are many opinions out there about whether you should self-publish or traditionally publish a book. Again, it's up to you to decide which course of action best suits your needs.

If you decide to go the traditional publishing route, get a good literary agent. An agent can help you land a publishing deal with the right publisher.

But of course, a successful book starts with a good idea and a unique voice. If you think you have something to share with the world, start working on your book today.

Published on: Jan 24, 2017
The opinions expressed here by Inc.com columnists are their own, not those of Inc.com.