For TJ Klune, writing has always been essential.

"I knew I was queer by the age of 10," says the 42-year-old author. "I was an effeminate kid in rural Oregon in the '80s and '90s, so you can imagine how that would go." He also had undiagnosed ADHD, he says, which came with its own challenges, and grew up in an unsupportive household. Reading and writing were a crucial escape.

Klune attended community college for one semester, then got a job working as a claims adjuster at Geico in 2006. Determined to be a writer, he published his first novel through an independent publisher in 2011. "Bear, Otter, and the Kid" was a contemporary drama about a queer family. It "sold extremely well," he says, and helped open the door to a dream career.

He quit his insurance job in early 2016.

Klune has since written dozens of other novels for both adults and young adults, mostly in the fantasy and sci-fi genres. These include series like "The Extraordinaries" and "Tales from Verania." His 2020 release, "The House in the Cerulean Sea," was a New York Times bestseller and and won a number of awards, including the 2021 Alex Award, which recognizes books for young adults.

His latest novel, "The Bones Beneath My Skin," a supernatural road trip thriller, is set to be released on Feb. 4, 2025.

Here, Klune discusses the moment he decided to take the plunge into full-time writing, what it's like to find success and advice for others hoping to follow in his path.

CNBC Make It: When did you know it was time to quit your job at Geico?

Klune: One of the big executives from the company came around and was touring the office in Virginia, and I was told to meet with them to go over the claims because I was one of the highest claims adjusters there. And after speaking with him, the man looked at me and said the most soul-crushing thing anybody can hear. He said, "You are very good at insurance."

And I realized right then — that was 10 years I'd been working there — I realized right then, I had to take a chance. I had to take a risk. I couldn't keep doing this. So the next week, I walked in and gave two months notice, and I left in February of 2016.

You wrote many titles between your first release and quitting. Had you considered quitting before?

I think there was always an inkling in the back of my mind, before that conversation even happened, that I was gearing up to do this.

So I made sure I had a nest egg set aside, a years' worth of salary, to make sure that I could survive that first year. And if something bad happened, if my books didn't sell for some reason, my career tanked, at least I would have something in the bank to help me survive that first year.

That level of planning was absolutely necessary.

You've been writing full time ever since. Do you feel like you've made it?

What does making it mean? I've been very lucky in that I've been on bestseller lists. My last novel just debuted at No. 1 on the New York Times. I make a good living. I get to meet very interesting people.

But here's my thing: I want to be a better author than I am currently. I will never be the world's best author, and I don't want to be. I just want to get a little bit better each and every day. So that's what I focus on.

What does being a better author mean?

It means taking chances.

I want to write books that have footnotes. I want to write books that have notes in the margins and little doodles and everything like that. I want to write stories in non-conventional ways. I want to play with the idea of conventional narrative and structure.

What did you do with your first big paycheck as a writer?

[In 2013] I got a quarterly royalty check for $8,000. And I thought I was on top of the world. I was like, this is it. And so what did I do? I used that money to lower my debt … credit card debt, medical debt.

Even though I only went to a semester of community college, I still had student loans because I couldn't afford even that semester of community college.

Is there a best piece of career advice you've ever gotten?

You will have people that love your books. You will have people that like your books. You will have people that dislike your books. You will always have people who hate your books.

Focus on the former, don't focus on the latter.

And never, ever write what you think people want, because people are fickle. Write what you want and let people find your story.

What's one thing you want people to know about the career of a fiction writer?

No two careers are the same. What works for one person will not work for another. You have to plan out and define your own career. You have to find out the path that works for you, whether it be self-publishing, whether it be independent publishing, whether it be getting an agent and going into traditional publishing. Each has their own pros and cons.

Final words?

We are seeing more and more publishers picking up queer authors, both on the independent scene and the traditional publishing scene and giving them the audience they deserve.

I can't tell you how many queer men in their 40s, 50s, 60s and 70s who've written to me saying, after reading one of my books, this was the first time they got to see queer people be happy in a story. And that is the best thing in the world.

So if you are a queer person who has an idea for a book, now is the best time to do that.

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