NEW YORK (MainStreet) -- Ten or 20 years before retirement, you might get a queasy feeling about the future. You’re a bit behind on building the nest egg and just aren’t sure you’re going to be able to pull it off. But think back to those early days after college when you were building a career and making do with whatever money you could scrape together. There are lessons to relearn from those ramen noodle days.

These are the financial habits that many under-40 adults still live by. Millennials, steeled by adversity, offer some valuable financial attitudes that just might help Gen X-ers and Boomers plan for retirement.

Live like you’re broke – Millennials live like they’re broke, probably because so many of them are. Bottom line: they’re a frugal bunch. Two-thirds of Gen Y have an established monthly budget that they try to live by, according to The Principal Financial Group.

Use online tools and apps – Millennials are noted for their research -- poring over online reviews and price comparisons before making a purchase means they know how to find a bargain. In fact, 57% of Millennials compare prices in-store before pulling the trigger on a purchase, according to AIMIA, a Montreal-based research firm. Millennials seek products that offer maximum convenience for the lowest cost, the study says.

Pay off student loans – We all know about the student loan debt debacle. But the thing is, one-third of Millennials are paying off that debt with the cash flow from their current jobs, according to Millennial Branding. The Government Accounting Office says adults 65 and over carry $18 billion in student loan debt themselves. Gen X-ers and Boomers should make it a priority to retire their debt before they retire.

Cut the cards, use cash – A Bankrate survey found a surprising 63% of Millennials don’t carry a credit card, preferring to use debit cards and cash instead. Research has also found that we spend less when using cash rather than credit.

Don’t live alone – This is a generation known for taking back the family’s spare bedroom. There is no shame in having a roommate -- or moving back in with family – to lower your cost of living. By 2010, nearly one-third of Millennials chose to live at home with parents, according to Goldman Sachs. Retirees can take a similarly flexible attitude when it comes to their living arrangements. That’s what friends and family are for, right?

Experiences over things – This is a generation famously driven by experiences. An Eventbrite survey last year said more than three-quarters of Gen Y (78%) would choose to spend money on an experience or event rather than buying “something desirable” -- and more than half (55%) say they’re spending more on events and live experiences than ever before. While concert tickets and exciting vacations don’t come cheap, research says accumulating memories rather than merchandise makes us happier. And memories usually last longer than stuff, too.

Be a good saver – A Harris Interactive survey last year reported most Millennials aimed to reduce spending on eating out (60%) and entertainment (55%) while saving or investing more money (64%). The previously mentioned Principal survey also revealed that over half of Millennials (57%) have an emergency savings fund and nearly two-thirds (63%) started saving for retirement before or at the age of 25. Gen X-ers and Boomers: a show of hands for who can admit the same?

Rent, don’t own – Gen Y has been slow to buy homes, cars and even music. The sharing economy means you can pay for access when you need it, rather than own. In a Goldman Sachs report, economist Jeremy Rifkin is quoted as saying, “25 years from now, car sharing will be the norm, and car ownership an anomaly.” Millennials often prefer to live in convenient locations, close to amenities – and use public transportation. Nice habits for retirees to adopt, too.

Focus on wellness – And for many retirees, the biggest expense will likely be health care. For Gen Y, a healthy lifestyle is paramount. According to, Gen Y-ers are exercising more, making healthy diet decisions and – once again – using apps to track their progress and find the healthiest foods.

Adopting some of these financial best-practices won’t turn the clock back to your younger days but might push your retirement date forward.