Many of us look forward to retirement and the opportunity to enjoy a lifestyle devoid of work-related demands. It's unfortunate, then, to learn that 28% of millennials are convinced they'll never manage to retire, according to data from TD Ameritrade.

On the one hand, this sentiment actually makes sense. Countless younger workers today are saddled with student debt to the point where it seems unshakable. Throw in the fact that younger workers tend to earn less than their older counterparts and their paychecks are often eaten up by debt payments and living expenses, and it's no wonder so many have written off retirement completely.

Young male professional at a laptop

IMAGE SOURCE: GETTY IMAGES.

Though the idea of ever establishing enough of a nest egg to retire might seem undoable, one thing younger workers need to remember is that they have an extremely valuable weapon on their side: time. And if they take advantage of it, they just might manage to retire after all.

Start saving as early as you can

If you'd rather not resign yourself to the notion of never retiring, then there's one thing you need to do: Start saving money now. In the aforementioned survey, younger workers said they planned to start saving for retirement at an average age of 36, but if you're in your early 20s and are already working, you have a solid opportunity to begin even sooner.

Remember, the longer a savings window you give yourself, the more wealth you'll have a chance to build over time, even if you only manage to part with a small amount of money each month. The following table further illustrates this point:

If You Start Saving $200 a Month at Age:

Here's What You'll Have by Age 70 (Assumes a 7% Average Annual Return):

25

$686,000

30

$479,000

35

$332,000

40

$227,000

TABLE AND CALCULATIONS BY AUTHOR.

As you can see, setting aside just $200 a month over 45 years gives you a good chance of retiring with $686,000, which is certainly enough to enable you to leave your full-time job behind should you choose to go that route. And while you'll clearly be in much better shape if you manage to accumulate $686,000 as opposed to just $227,000, even the latter might do the trick of allowing you to retire in some capacity.

Live below your means

Where will the $200 a month in our above example come from when your paycheck is currently maxed out? It might boil down to re-examining your budget and making some sacrifices to free up that cash. Downsizing your living space, getting rid of a car and taking the bus, or cutting back on restaurant meals are all viable means of significantly slashing your monthly bills, so choose the expense that'll impact you the least and go with it. Or leave these spending categories alone and play around with other expenses. Chances are, if you really look at your budget, you'll manage to find some wiggle room, and once you do, you'll be better positioned to save.

Of course, if you really don't want to mess around with your living expenses, you can always consider a side hustle instead. Working a second job might give you the money you need to build a decent amount of savings, and as an added bonus, it might open the door to different career prospects down the line.

Finally, remember that retirement doesn't have to be an all-or-nothing prospect. You may come to find that you're unable to go without some sort of income-earning activity when you're older because your savings aren't adequate, but that doesn't mean you can't scale back from 40 hours or more per week to a part-time role. Furthermore, if you take on a second gig during your working years, it might evolve into a money-making opportunity when you're older, and one that allows you to mostly free yourself from the daily grind.

If you're willing to be flexible in how you define retirement, there's a good chance you'll come to experience it in your own way. And that's a far more encouraging prospect than never managing to retire in your lifetime.

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