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This Teen Social Media Maven Joined Instagram When He Heard His Sister Had 1,000 Followers. Now, He Has Millions of His Own.

Declan Mortimer's journey provides key lessons for entrepreneurs of any age.

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Never let anyone tell you how to live your life. That was the biggest lesson that teenage entrepreneur Declan Mortimer's parents taught him growing up and something that he lives by today, as a social media maven. You might not recognize his name right away, but for the Instagram-obsessed, chances are you've run across one of his ever-growing profiles.

Josh Edelson | AFP | Getty Images

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His journey began as an inquisitive 9-year-old, with Mortimer growing intrigued with a social media application that he saw his mother scrolling through, something called Instagram. Like most kids his age, he quickly lost interest in the app in favor of video games and fun … at least until he heard that his sister had gotten over a thousand followers on her account. Hearing that number, which seemed so big, stimulated Mortimer's interest. He decided to dive headfirst into the world of social media marketing.

Unfortunately, he was still too young to have a personal Instagram page of his own, so Mortimer changed the way that he looked at this obstacle. He made it into an opportunity.

Rather than lie about his age to make an account, Mortimer focused on creating an account geared towards Tumblr posts and things that he found "cool." He challenged himself to not only accrue more followers than his sister, but he set a goal of attaining 10,000 followers.

Profile building

Then, Mortimer went to work. He put his intention on providing great content to his followers and pursuing his Instagram potential every day. He hit 10,000. He hit 50,000. He hit 1 million followers.

After that, he learned his next lesson: Businesses need to evolve.

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Declan thought that his content had gotten a little stale, so he decided to evolve past the basic Tumblr posts he had focused on. He transformed his account into the laugh-focused @ComedySlam, and this pivot led to even more opportunities.

After re-aligning his account to comedy content, Mortimer started to get companies reaching out to get his help with their social media marketing campaigns, leveraging the audience he had worked so hard to build. These companies would simply have Mortimer post an ad in exchange for an iTunes gift card, an easy deal for a young teenage gamer.

Hobby becomes a business

Before long, companies of all sorts and sizes began making offers to leverage the @ComedySlam following. When Mortimer realized that he could use this profile to get income other than just iTunes gift cards to fund his gaming habit, he got help from his parents setting up a PayPal account and got his business registered as a limited liability corporation.

He kept putting time and effort into the @ComedySlam account, growing its followers and his own revenues. It was at this time that Mortimer learned another lesson: In business, you have to crawl, then walk and then run.

With his main account approaching 10 million followers, his other "Slam" accounts growing rapidly and a six-figure income from his part-time venture, Mortimer had to make a decision. With the support of his parents, he decided to drop out of high school to operate his social media advertising business full-time. He still works on his studies, of course, but now he has more time to deliver ad campaigns for brands and influencers such as Disney Maker Studios, Gary Vaynerchuk, Tai Lopez, Fashion Nova and more. He is even helping his parents launch their own line of hair care products, Mister G Gel.

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Three takeaways from a teenager

While Mortimer's path to success might be vastly different from the path you have set for yourself, there are still some important takeaways from this young entrepreneur's story which you can apply to your own life.

Live your life for yourself, not for others. While other people might have your best interest at heart, you have to make decisions about your life and business for yourself. Be accountable for your own decisions and your own happiness.

Businesses need time to evolve. Entrepreneurs need to ensure that your doors are open tomorrow so that your business can evolve and grow over time.

Crawl before you walk, before you run. It takes time to understand an industry or business, so start out slow and work to progress. If you try to run from the beginning, you are likely to run right into a wall.

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