This 3-step practice, sworn by a former Google exec, is key to building your reputation: I 'continue to do it every single day'.

Your reputation is crucial in advancing your career, and it's never too late to work on your personal brand, according to Maha Abouelenein, a strategic communications expert and author of "Seven Rules of Self-Reliance." Abouelenein, a former Google executive, is the founder and CEO of global communications firm Digital and Savvy.

According to Abouelenein, building a professional reputation involves three key steps: delivering high-quality work, providing value to others, and nurturing strong relationships.

"Investing in your reputation is crucial," she advises CNBC Make It. "It's the only asset you truly own, and it's essential for achieving success."

1. Do good work

The public relations expert, born in Minnesota, began her career as a promotions planner at General Mills before moving to Egypt and Dubai to hold managing director and C-suite roles at Weber Shandwick and Google.

Establishing credibility was crucial for her success as a woman executive in a male-dominated industry. Abouelenein often felt the need to "step it up a little bit more so I can be heard."

In 2014, Digital and Savvy was launched, a company that collaborates with prominent brands such as Netflix and Uber, and notable individuals like actress Halle Berry and entrepreneur Gary Vaynerchuk.

"Instead of promoting my reputation, I decided to let my work speak for me. I would consistently deliver results, be reliable, loyal, thoughtful, and strategic. This way, people would understand who I am and what I do."

2. Add value

To increase your worth at work, Abouelenein advises adhering to these four principles.

1. Collaborating and putting in the effort to solve problems is important.
2. Offer knowledge and assistance to those around you by sharing insights and ideas whenever possible.
3. Back up your ideas with facts to improve your credibility
4. Anticipate the needs of your boss, manager and colleagues

If you know your coworker is overwhelmed, consider offering to take on a task or two. If your boss is onboarding a new employee, volunteer to show them the ropes.

Consistently delivering something unique and valuable to someone requires going above and beyond what is expected, according to Make It.

3. Foster strong relationships

Having individuals who can attest to your credibility is a great way to establish a strong reputation.

"I recognized the significance of cultivating strong relationships early on, as it fosters trust and creates a bond," Abouelenein remarks. "As a result, I have devoted my entire life and 30-year career to nurturing these relationships, and I continue to do so daily by making deposits into others' trust accounts."

Life coach Francesca Hogi advised CNBC Make It that reaching out to someone only when you need something from them can make them feel taken for granted, which successful people avoid.

Instead of immediately asking for things, be good intentioned by being curious about people's backgrounds and insights, practicing active listening, and following up with them afterward, says Abouelenein.

Sending a "Happy Holidays!" message or a "Get well soon!" text is a kind gesture that doesn't require extra effort.

To establish a strong reputation or personal brand, authenticity is key, according to Abouelenein. Consistency and having a clear purpose are also essential.

To become a successful and confident communicator, enroll in CNBC's online course, "Become an Effective Communicator: Master Public Speaking." Our program will teach you how to speak clearly and confidently, manage your nerves, choose the right words, and use effective body language to make a great first impression. Sign up now.

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