Unlike best-selling author Robert Kiyosaki, most people didn’t have a “rich dad” mentor while growing up. For instance, I came from a working-class family, so my exposure to successful business leaders was limited. But looking back, I can identify five groups of people that shaped the businessman I became–family members, friends, TV characters, teachers, and authors.

These people weren’t my mentors by design, but without them, I would’ve missed out on lessons about toughness, honesty, and ingenuity. And more importantly, I wouldn’t be the leader I am today. Great mentors can take on many roles, but here are the five key insights my mentors taught me:

1. Be tenacious. There is a connection between physical and mental labor. I learned that from splitting wood and baling hay with my father. The toughness and discipline required to finish a physical task can also be used to tackle mental challenges, such as pushing through an off-kilter project.

Look at the people in your life who’ve overcome great physical challenges. Did they throw up their hands and quit? Of course not! Instead, they worked hard and pressed on. Learning this tenacity has helped me push through failures, and it can do the same for you.

2. Seek out honest friendships. The concept of friendship has changed a lot lately, but when I think about my friends, I don’t think of my Twitter followers. I picture the people with whom I share an authentic connection.

Your friends can (and should) influence your life. Focus on the friends who actively listen. They’ll talk about what’s really going on and help you jump some of life’s hurdles along the way.

3. Learn to solve problems. I grew up watching re-runs of TV programs featuring characters such as Andy Griffith, Charles Ingalls, and Ben Cartwright. The characters taught me a great deal, and I watch their shows today with my kids.

As a leader, you have to face difficult challenges. If you work hard to overcome them, then there’s always a lesson to learn. Even though it might sound a bit silly, don’t discount the challenges faced by your favorite fictional characters. The lessons they’ve learned might apply to your life as well.

4. Become fully engaged. Some of the minor tweaks my teachers made during my early years continue to affect how I learn today. For example, one teacher recognized that I had trouble learning in a lecture setting. She decided to change things up for my benefit and would occasionally open up classroom-wide conversations after lectures. My teacher taught me that new information could be fun when I learned it in a way that suited my needs.

I still enjoy learning by diving into projects that will force me to learn the subject matter better. Look back and see how you learned most effectively growing up. Revisit those methods to see your comprehension improve.

5. Absorb knowledge through books. I didn’t have access to business leaders in the beginning of my career, so I turned to books. If you ask me which business book will put you on the path to success, I’d say you’re missing the point of reading.

John Donahoe, president of eBay, has said, “Pursuing a full life and pursuing balance is a journey and not a destination.” I think the same is true of reading. There’s no book that contains the secret to success. If you read a wide range of topics, you’ll find valuable nuggets of wisdom during your journey.

You can’t rely on my mentors–I’ve only been able to identify them through self-reflection, after all. You must seek out your own. Don’t let your influencers just happen. Be the architect, and line them up to help you achieve your idea of success.