Congratulations on graduating college and earning the most expensive (and arguably most important) piece of paper you'll ever own in your life. Now what? The real world is sinking in and some may be racking their brains for the Spark Notes version of their commencement speech to find inspiration and encouragement.

Abby Wambach, soccer champion and activist for pay equality and LGBTQ rights, spoke to the 2018 women graduates of Barnard College. While some commencement speeches tend to be overly optimistic, I found it refreshing that she hit on the reality of what grads can expect in the real world. Life isn't going to be all unicorns and rainbows. You're going to fail, you're going to be faced with adversity, and you're going to have to fight for what you want. And that's okay.

These four lessons are ones that have stayed true throughout my professional career and to this day, continue to guide me through the professional challenges that sometimes arise.

1. Hard work is okay

There will be long hours and there will be moments you'll want to crumble. Whether it's during your journey of applying to your first job, or at your first, second, third or fourth job, you'll work hard. But, we all know that with hard work, comes reward. Yes, there are times where overworking can become unhealthy. That being said, hard work, overcoming adversity and tackling challenges are experiences that will teach you about yourself, your tenacity and your grit. It's what prepares you for the next challenge ahead.

2. Failure is fuel, and fuel is power

I can't take the credit for that powerful header, but Abby is right. How would you ever learn if you didn't fail? At HubSpot, we like to say, "fail fast, and fail often." We've even created the Failure Forum with the objective of showing that failure is not only welcome, but encouraged.

By talking in detail about what went wrong, what it felt like, and how the experience got you to think differently, you quickly learn from failure. When you decide to embrace your own failures that you will experience throughout your career, it will empower you to continue to be bold, be innovative and to take risks.

3. There's no rulebook

I'll let you in on a little secret: there's no handbook for life. Your dream job may turn out to be just a stepping stone in an even more prolific career. You may find that the subject matter you studied so hard in school is actually not what drives your passion anymore. There isn't a handy syllabus that's going to tell you exactly how your job should be done -- it's up to you to be resourceful and navigate through it.

Embrace the uncertainty. Find a company that will encourage curiosity and provide you with the ability to create your own destiny. There's no right way to be successful in your career, but rather many paths that lead to new experiences that will shape you to be the best professional you can be.

4. The student/teacher relationship is blurred

The student and teacher relationship will be blurred from this day out. You'll learn from those more junior than you, you'll learn from your peers, you'll learn from those not in your industry, and you'll learn from people you pass by in a fleeting moment. Embrace that everyone will be teaching you something.

When you think you've become an expert is actually the moment you need to become a student again. Always be growing, always be learning, and always be teaching. You are a teacher, too, and you have more valuable knowledge than you know. But, don't forget to listen.