Maybe you won’t hit an actual million in retirement savings. But if you change your strategies now, it’s definitely possible to double or triple the size of your retirement account.

It all depends on how much you learn and how much you invest.

You can take 100 people who are the exact same age and find wildly different financial habits and situations. A 23-year-old could be struggling to pay off student debt on a slender starting salary or strolling down Easy Street with a high-paying job and generous parents. Another might be in the process of successfully knocking down credit card debt by living frugally.

As Americans, learning about money depends on highly specific personal situations. Only a handful of states require high school students to study personal finance, according to the Council for Economic Education. In other words, if you didn’t grow up with some solid lessons in money, you’re in the dark about basics — and most people are left to figure it out on their own.

At any age, people might think investing is difficult to learn and impossible to understand.

Well, think again.

People invest at all income levels and all ages. They are not smarter than you. They are not always richer than you. They just possibly know a few things you don’t know.

They know how to handle their money. They have goals. They know that investing in equities has a higher return than keeping your money in a savings account. They know that small amounts add up. And they know that good habits beat good luck anytime.

They also know you can’t earn or save your way to wealth — but investing will get you there.

Try this millionaire calculator from Bankrate, the personal finance website, to see how far your savings rate will get you. For instance, if you’re age 30 and already have $10,000, you’ll need to save $519 a month to hit $1 million by age 65.

That assumes a 7% rate of return and inflation of 2.9%. Starting 10 years later, at age 40, you can save twice as much and by age 65 you’ll reach $841,744.

No matter how old you are, it’s never too late to start.

Whether you’re just out of college or staring down the last of your working years, here’s what to do.

Ditch your money drama

Your 20s are the starter years. No matter your career, you’re just starting to spread your wings. At the end of that decade, you might be considering marriage, children and a home. In the beginning, though, you’re relatively unencumbered.

That makes it the perfect time to figure out your finances and develop healthy habits for a good foundation.

First: Master your cash flow, says Douglas Boneparth, a certified financial planner and president of Bone Fide Wealth. It’s not difficult, but it is time-consuming.

Look through past credit card and bank statements to see what you spend on meals out, groceries, entertainment, rent, utilities, transportation and debt repayment. Compare spending with income and see what’s left over, if anything. Learn to spend more consciously and see where you can make some cuts.

Your other task: Learn to save. It’s all about attitude. From your own spending history, find one or two items you can save on. Maybe you’ve been eating in restaurants three times a week. Cut it to two or even one — those meals are the amount you can save. Use a separate account. Earmark it for a vacation, holiday gifts or use it to pay down debt.

If you have a workplace retirement plan, use it. Don’t be scared off by recommended percentages. If you’re struggling with student loans or credit card debt, save 1% of your income. Small amounts add up over time; your job is to create your own saving mindset.

If you don’t know what investments to choose, consider a target-date fund. It’s a simple way to make sure you are diversified.

No workplace plan? Open an Individual Retirement Account and set your deposits on auto so you don’t have to think about it.

Wow, you’re 30!

You feel awed and old at the same time. But you probably also feel more confident. (Admit it: You were always freaking out a little bit in your 20s.)

Your 30s are crazy busy, says Boneparth. Between starting a family and buying a home, “things are disproportionately more hectic,” he said. The foundation you developed earlier really pays off: “This is where you want to get serious about consistently saving.”

Since you are likely moving into a more mature career stage, you’re going to have far less time if you’re growing personally and professionally.

If you haven’t already started, now is the time to begin investing.

Beginning investors should learn as much as possible, says Tony Steuer, a personal finance educator and author of “Get Ready! A Step-by-Step Planner for Maintaining Your Financial First-Aid Kit.”

Need definitions on the basics? For a clear picture of stocks, bonds, mutual funds and exchange-traded funds — among other terms you’ve likely heard — the Securities and Exchange Commission explains it all in simple language.

Watch out for misconceptions. According to Priya Malani, a founding partner at financial planning firm Stash Wealth, all investors, no matter how experienced they may be, tend to misunderstand the basic premise of investing.

Malani likes to demystify the concept and explain the purpose of investing. “We teach that investing is a way for your money to grow over time, not overnight,” she said.

Remember, too, Malani said, “Investing itself isn’t the end goal but rather a means through which to achieve your goals.”

If your company matches your 401(k) plan or 403(b) contributions, don’t miss out. “This is essentially free money,” Steuer says. “Taking full advantage of the employer match doubles your savings.”

What to do in your 40s

One thing that’s definitely on the minds of people in their 40s: How am I doing?

By now, you definitely need to be stashing a solid percentage of your income aside for retirement.

If you are dissatisfied with your financial progress, there is still time to step it up. It can be a tough spot to be in, but the solution is to increase savings and be willing to take on some risk in a diversified portfolio.

At age 40, according to Fidelity, you should have saved about three times your annual salary in your retirement account. If you make $60,000, your goal should be to have $180,000. By your mid 40s, you’ll want to have four times your salary saved.

There’s never a good time to save, but as you get older, you also realize that retirement is coming. Even though you might be paying or saving for college tuition, caring for your parents, this is a time to save and invest aggressively.

“This age group needs to immediately max out their 401(k) to the degree they’re able to,” says David Schneider, a CFP and founder of Schneider Wealth Strategies. He recommends investing fairly aggressively: “Retirement could be 20 years away,” he said. “There’s plenty of time for the stock market to recover [from the inevitable downturns].”

Make sure your cash reserve is always healthy. “If it gets used, top it off,” Boneparth says. At this point, you definitely know what your goals are, and hopefully you have achieved many of the short-term ones.

Boneparth recommends maximizing the amount you save and invest toward reaching long-term goals: “Saving north of 15%, 20% would be fantastic,” he said, “and more would be better. But a 20% savings rate is respectable.”

Retirement is looming

In your 50s and beyond, if you’re well below what you’d like to have for retirement, there are no magic answers.

People who haven’t saved enough may have to face some uncomfortable truths. Some possibilities to scout, Boneparth says, are the option of working longer or at least working part-time.

Be honest and address your spending. Maybe you can’t afford the lifestyle you’d prefer at your level of savings. People have to make tough decisions about how much to save versus how comfortable a life they’d like. Finding a cheaper place to live is sometimes a way to go.

If you can funnel a lot of your salary into a workplace plan, that is another strategy. “At this age, you can do catch-up contributions, ” Boneparth said. “You might need to be more aggressive than you normally would be. You might invest with a higher percentage of equities.” Some people tend to shift more into bonds in their 50s and 60s, but those who need to catch up may need to take on more risk and stay invested more like someone in their 30s and 40s.

Go back to the fundamentals. If you haven’t gotten the upper hand with your cash flow, revisit those basic elements of income versus spending.

Make sure your insurance is adequate to your needs and that you have a healthy emergency fund.

“It’s never too late to start building that foundation,” Boneparth says. “It might come at the cost of having to push out goals further. But if you haven’t started saving, now is the time to do that and catch up.”

This article is part of the "Invest in You: Ready. Set. Grow." series from CNBC and Acorns. Disclosure: NBCUniversal and Comcast Ventures are investors in Acorns.

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