Your 20s go fast. You may be focused on finishing school, starting your career, dating, or adjusting to living on your own and becoming independent. It's so easy to let this decade go by without developing a focused financial plan. Then, one day you could wake up and realize "What just happened? I'm 30 and have no money saved!"

My niece recently turned 30 and faced this type of financial reckoning. Her 20s flew by in a flash, without any financial focus. She was contributing the minimum to her 401k, but she also got into credit card debt and had no other savings. Suddenly, she turned 30. She developed a serious relationship, and they had the money talk. They both realized that if they wanted to take their relationship to the next level, they needed to start "adulting" financially. She asked me for ideas on how to get started. So, we sat down together and did a deep dive on her money beliefs, financial goals, spending and saving activity, and understanding of investing concepts and solutions.

My niece realized that she let her 20s go by without being purposeful. Here's what she could have done differently to potentially maximize her future, and ideas for you to consider.

I get it. When you are in your 20s, you probably aren't thinking about retirement. Try looking at it this way: Consider investing now so you can live your dream life later. You are saving and investing for flexibility and choice in your future.

I know you may have multiple financial priorities, and it can be hard to pay off student loans, cover everyday living costs, and try to save for a car or home, let alone set aside a percentage of your paycheck for retirement.

So, this is what I told my niece. Consider prioritizing investing now­ because the earlier you start, the less you have to save each year due to the power of compound growth.

Here's an example of how compound growth could help you. In these scenarios, we use a 6% annual growth rate on investments. The below example is for illustrative purposes only.

• Madison starts investing $5,000 a year when she's 20 years old. She does this for 45 years, earning an average of 6% annually. When Madison turns 65, she will have accumulated over a million dollars—or $1,063,717.57, to be exact.
• Hannah doesn't start saving until she's 40. In order to achieve a million-dollar nest egg by age 65, she would need to save $20,000 a year, also earning an annual average of 6% to accumulate $1,097,290.24.