Are You Actually on Track to Retire Well? A Financial Expert Reveals the Critical Milestones to Hit at Every Age — Plus 3 Common Oversights. Stacey Black, lead financial educator at Boeing Employees Credit Union (BECU), breaks down how to have a comfortable retirement.

Retiring early might be a dream for many Americans, but it's a reality for few. Nine out of 10 people aged 50 to 59, just several years shy of claiming Social Security, are still working, according to retirement data from The Motley Fool.

Many people begin saving for retirement too late — or not at all. A survey conducted by OnePoll on behalf of Prudential found that 52% of respondents have fallen short of the savings goals they planned to have by now, and 26% never started planning for their retirement, per Talker.

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Preparing for an ideal retirement can look different for everyone, often depending on age, income and financial goals. However, with the typical American worker believing they'll need $1.46 million to retire comfortably, one thing's certain: The earlier you start saving, the better.

"It's important to talk to an advisor who can help create a tailored path specific to your financial goals."

Entrepreneur sat down with Stacey Black, lead financial educator at Boeing Employees Credit Union (BECU), to learn more about the retirement milestones that matter most over the years.

^{Image Credit: Courtesy of BECU. Stacey Black.}

"For all ages, it's important to talk to an advisor who can help create a tailored path specific to your financial goals and set you up for a realistic retirement lifestyle," Black says. She suggests asking yourself what you want in an advisor to help inform your decisions and considering their experience, qualifications, credentials and approach.

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Here are Black's general guidelines to keep in mind as you prepare for retirement at every age:

How to prepare for retirement in your 20s

• Save three to six months' worth of living expenses so you can be prepared for financial challenges without draining your retirement savings.
• Start contributing to retirement accounts as soon as possible. Open a 401(K) or IRA as soon as you start working. Even small contributions can grow significantly over time due to compound interest.
• Consider taking on a side gig to increase your income and then apply it towards savings or retirement.
• Think about major expenses like buying a home or having kids. Plan ahead so you won't need to tap into your retirement fund later.

Related: 8 Ways to Set Yourself Up For Financial Freedom in Your 20s

How to prepare for retirement in your 30s and 40s

• Resist the urge to increase your spending as your income grows. When you get a raise, direct it to your savings or retirement accounts instead of spending more.
• Make sure you're taking full advantage of employer-sponsored retirement plans. Many employers offer a matching contribution, and if you're not getting the full match, you're essentially leaving free money on the table.
• Reevaluate your retirement goals and adjust as needed. If you're behind, consider making more aggressive contributions or adjusting your retirement age or lifestyle expectations.

Related: Is Early Retirement Really Out of The Question For You? Here Are 10 Money-Saving Tips That Can Help Make It Happen.

How to prepare for retirement in your 50s

• Take advantage of catch-up contributions, which allow people 50 or older to make additional contributions to their 401(K) or IRA accounts. This can help boost your retirement savings and can have potential tax advantages.
• Try living on your retirement budget a few years before you retire. This can help identify potential shortfalls or lifestyle adjustments that may be needed.

Related: 8 Fun and Fulfilling Ways to Retire by Age 50

"What seems like a comfortable nest egg today might have less of an impact once you're further into your retirement."

Black also warns against a few common oversights when it comes to getting ready for retirement. First, don't forget to factor in inflation for long-term financial goals.

"What seems like a comfortable nest egg today might have less of an impact once you're further into your retirement," Black explains. "Plan for rising costs and ensure your investments are structured to grow and outpace inflation, providing financial security throughout your retirement years."

Related: More Americans Are Retiring Abroad, Without a Massive Nest Egg — Here's How They Made the Leap

Additionally, remember that you might have to cover health insurance costs until you qualify for Medicare — and consider that the earlier you tap into Social Security benefits, the lower your benefits will be.