So you didn't get started on your retirement savings at 20, but it isn't too late. While advisors warn that if you don't start early, you won't be able to save enough, that doesn't mean that you shouldn't start at all.

Better late than never.

Millions of Americans are over 40 with no substantial retirement savings. The key is taking full advantage of every penny between now and retirement.

First, you need to sit down and estimate how much money you will need to retire. Don't focus on how to arrive at the number; there are a lot of conflicting methods. You don't need to necessarily set the round $1 million figure as a goal, either. Simply get a good ballpark figure by looking at what bills you pay right now and what you intend to pay in retirement. There are a few online retirement calculators that may be useful.

Once you know how much money you will need in retirement, you need to see what income you will have. This is money coming in from sources other than savings. For example, what is your expected Social Security benefit? Do you have a pension from your employer? What is the expected value of your 401(k) at retirement? Always consider that you will have less than average growth to avoid overestimating.

Now you will need to look for ways to make up the difference between your retirement income and expected expenses. The simplest way is to start contributing the maximum amount you can to your employee 401(k), or like, plan. This is money that comes out of your paycheck without you ever seeing it. It is easily forgotten, because you don't ever actually have it in your hand.

If your employer matches a percentage of your contribution, that's free money for you.

If you come in under certain income thresholds, you may qualify to contribute to a Roth IRA as well. The contribution is not tax free, but the earnings are when they are withdrawn in retirement.

If you are under 50 years old, you can still afford to be a little aggressive in your investments. You still have a decade or two to let your retirement earnings grow, so don't be afraid of stocks and mutual funds.

You need to cut back on your spending as much as possible. Go ahead and try living on your expected retirement income. This will let you see if what you estimate is actually possible. You may find that taking on a second job now will help prepare you financially for retirement. You could save a lot by dedicating all of the income from a second job to your savings.

Consider making debt elimination a main priority. Paying interest on your debt is zapping your potential retirement savings. Paying only the minimum payment on your credit cards is a horrible idea. Start paying off your credit cards right now. Make that number one. Then start saving for retirement.

You want to eliminate as much debt in retirement as possible. Some people successfully have mortgages in retirement. Others enjoy the freedom of owning their own properties. The amount of your mortgage could make or break you. If your children are leaving the nest soon, you might consider downsizing to a smaller, less expensive home.

The older you are, the harder it is to save. But it is possible. Get started now -- you don't have a penny to lose.