My favorite thing about graduation season is all the brilliant advice commencement speakers share with bright minds heading out to conquer the world.

As a former executive who studies what makes people mentally strong and shapes successful leaders, I've also collected a lot of advice for new grads over the years.

For my book, "The Mentally Strong Leader," I asked 3,000 highly successful senior executives what they wish they'd known when they started their careers. Here are the top five themes that came up in their answers.

1. Nobody else owns your career—you do

Don't assume anyone else is sitting around, plotting your career trajectory. It's up to you to take ownership.

Clarify and make known your short, medium, and long-term career goals as soon as you can. When you've earned the right, ask for what you want. Stay where you're appreciated if it fits your plan, and leave places where you're not valued.

Along the way, stay focused on pursuing the career that you want, that fulfills your sense of purpose — not the career someone else expects of you. A career isn't always a ladder with a series of promotions up to a clear destination. As one executive told me in an interview, "a career can also be a river to ride, with lots of lateral twists and turns."

2. Find the good in every assignment

This advice came up early and often in my survey and interviews. It's also one of the first pieces of career advice I give when asked. 

In one of the most influential jobs I ever had, I worked for a terrible boss, doing work I didn't like. I acted like a victim: "Feel sorry for me, I'm stuck in this terrible role!" Then a mentor yanked me aside and reminded me that I won't love every job I ever have. 

Be open to finding the hidden gems of personal development, and make the most of an assignment. I learned what not to do as a boss — insights that shaped the kind of leader I would become — and built tremendous resilience before moving on to a better job in a healthier environment. 

3. The biggest career risk is not taking any risk

Sure, you could have a nice career playing it safe. But taking some calculated risks along the way vastly increases your chances of having a fulfilling career.

Many executives shared that one of the smartest career risks they took was leaving a job that didn't align with their goals, even if doing so meant experiencing discomfort (like taking a pay cut or defying norms). If possible, make sure you have a plan to run to something exciting rather than just from something awful.

One executive described how she "transformed her life" by leaving her role as a scientist to become a real estate agent. And I left a high-paying, high-potential corporate job to go into professional speaking, training, and writing. It was the least safe, but best, career move I ever made. 

4. Show your character

Ever see a leader lose their temper, finger-point, or act unprofessionally in a tough moment? I bet you have, and that you haven't forgotten it. As I point out in my book, it's in times of adversity that your true character shows. The way you respond when things aren't going well makes a lasting impression.

When adversity strikes, one CEO told me, "be the calmest person in the room." Don't let your emotions hijack you, and avoid making uninformed assumptions. Speak in a controlled tone and try to project confidence. This keeps everyone focused on what must be done versus what might happen.  

5. Never stop learning

In many of my interviews, executives expressed this one as a regret. They wished they would have stayed committed to learning throughout their careers. 

To be more intentional about it, I created the "3C Exercise." Revisit it on a regular basis, like at the beginning of each year, or even each quarter:

1. Career: First, ask yourself what you can learn to advance your career? For example, you can take a communication class to improve your presentation skills, if you're being asked to speak at meetings more often.
2. Cause: Think about what you can learn to feed your cause, something bigger picture that's important to you. For instance, a core value of mine is kindness, so I like learning new things about co-workers to see how I can help or support them.
3. Curiosity: Finally, what could you learn to feed your curiosity? For example, maybe you want to take an astronomy class just because the planets fascinate you.

Scott Mautz is a popular speaker, trainer, and LinkedIn Learning instructor. He's a former senior executive of Procter & Gamble, where he ran several of the company's largest multi-billion-dollar businesses. He is the author of "The Mentally Strong Leader: Build the Habits to Productively Regulate Your Emotions, Thoughts, and Behaviors." Follow him on LinkedIn.

Want to boost your confidence, income and career success? Take one (or more!) of Smarter by CNBC Make It's expert-led online courses, which aim to teach you the critical skills you need to succeed that you didn't learn in school. Topics include earning passive income online, mastering communication and public speaking skills, acing your job interview, and practical strategies to grow your wealth. Use coupon code MEMORIAL to purchase any course at a discount of 30% off the regular course price (plus tax). Offer valid from 12:00 am Eastern Time ("ET") on May 19, 2025, through 11:59 pm ET on June 2, 2025. Terms and restrictions apply.

Plus, sign up for CNBC Make It's newsletter to get tips and tricks for success at work, with money and in life, and request to join our exclusive community on LinkedIn to connect with experts and peers.