If you're learning about how to manage your finances, you're going to come across a lot of "shoulds." You should only be paying this portion of your income toward you living expenses. You should have that amount in an emergency fund. You should forgo your delicious lattes and avocado toast. And when you're not doing what you "should" be doing — oftentimes because you're not able to — it becomes easy to ignore some of the advice altogether.

"There are all these rules of thumb out there," says Becky Krieger, a certified financial planner at Accredited Investors in Edina, Minnesota. "If they don't seem to apply to you or they seem unreachable, it can be frustrating."

One piece of advice you can't afford to ignore, however, is to start investing as much as you can toward your retirement as early as you can. "The earlier young people invest, the more time and compounding can work in their favor," she says. "Even if they start small, making progress toward long-term financial goals early is so important."

Evelyn Zohlen, a CFP at Inspired Financial in Huntington Beach, California, agrees. "How do you eat an elephant? One bite at a time," she says. "How do you get to the point where you're saving 15% of your income annually? One percent at a time."

Increase your savings rate methodically over time

Financial bigwigs often advise that you save 15% of your income to put towards retirement — a near-impossibility, oftentimes, for an early career worker balancing living expenses and paying down debt. But rather than waiting until you have the financial security to contribute that full amount, start by socking away what you can.

Start, if you can, with a contribution that allows you to maximize any matching contribution that your employer might offer in their workplace retirement account, such as a 401(k). "Find out what the match is and put in enough to get the free money," she says.

"However, if you can't put in enough, put in 1%," she says. "Then next year put in 2%. Do that every year, and next thing you know, you're saving 10%."

Crunching the numbers on retirement savings

Even if you start off small and gradually increase your contributions, over the long run, you'll come out just about as well as your peers who contributed more early on. Consider three friends: Regina, Gretchen, and Karen. All three earn $50,000 a year working at a firm that will match up to 5% of employee 401(k) contributions.

Over the course of their careers, they can expect annual wage growth of 2% and a relatively modest 5.75% annualized return after fees on their investments. All begin investing at age 25.

Regina is queen bee when it comes to saving for retirement. She contributes 10% of her salary from the start and earns the full 5% match from her employer, hitting the target of 15% savings throughout her career. By the time she's 65, her account would be worth $1.5 million, according to data from J.P Morgan.  

Karen starts at 3% of her salary and stays there. Her employer matches her 3% contribution, and by the time she calls it quits, she would have $610,000.

Video by Jason Armesto

Gretchen can also only afford to contribute 3% to start, but she increases her savings by one percentage point annually until she's saving as much as Regina. Despite Regina's head start, after 40 years, Gretchen is able to just about catch up, saving up $1.4 million for retirement.

That's pretty fetch, Zohlen says. "You don't have to sign up for 15% on day one," she points out. "Start tiny, and next thing you know, you'll have eaten the whole elephant."

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