Do-it-yourself retirement has arrived.

Employers are doing away with traditional pension plans that promised monthly checks for life. And Social Security? Who knows what may happen to it over the next 20 or 30 years.

That's why everyone needs at least some savings to ensure a secure and comfortable retirement.

But how much is enough?

Our 5-step plan will help you figure that out and develop a strategy to get the money you'll need.

WARNING! Don't be shocked if you're looking at a breathtaking number. A number that's so large you don't see how you could possibly save that much.

Here's the thing to remember: The more money you have, the faster it grows. It typically takes 10 years of saving and investing to obtain your first $100,000, but only half that long to save the second $100,000. (Look at our "You can be a millionaire" calculator to see how this works.)

Just don't get discouraged and give up.

According to the Center for Retirement Research at Boston College, 45% of working-age households are at risk of being unable to maintain their pre-retirement standards of living in retirement.

The segment of Generation Xers born from 1965 to 1972 is most vulnerable at 49%.

Baby Boomers aren't faring much better: 35% of Early Boomers (born 1946-1954) and 44% of Late Boomers (1955-1964) are at risk.

Here's what you need to do:

Step 1. Determine how much income you'll need during retirement.

Financial experts say you'll need anywhere from 70% to 90% of what you currently live on.

But with so many of us living longer, and facing larger medical and assisted living costs, there's a growing consensus that you should shoot for 85% of your current salary.

Estimate your current monthly or annual income and multiply by 0.85.

Example: If you're making $65,000 a year before taxes, you'll need $55,000 or $4,600 a month when you retire.

Step 2. If you have a pension, find out how much you're entitled to receive.

Corporate retirement plans that promised checks for life are the primary source of income for millions of current retirees. Many never saved a dime for retirement because they knew they'd be taken care of.

No more.

Most employers don't have, or are doing away with, these defined-benefit plans.

If you're a Boomer who's qualified for one, consider yourself lucky. You can probably count on receiving most of what you've been promised.

Go to your Human Resources Department, or any former employers with a defined benefit plan, and ask for an estimate of what your monthly check will be based on when you decide to start collecting benefits.

Ask them to run the numbers from the year you qualify to draw a check (usually when you turn 55) and the year you qualify for the maximum benefit (somewhere between 62 and 70).

Take the annual income you will get from your pension and subtract it from the total annual income you think you will need. The remainder will have to be generated from savings and Social Security.

Example: You're earning $65,000 a year and need $55,000 a year when you retire. You'll receive $18,000 of that from a pension, leaving $37,000 or 57% of your pre-retirement income to come from other sources.

If you're in Generation X or Y (today's 20-somethings born since 1977), don't bother.

You need to assume you won't have a corporate pension even if your current employer still offers such a plan.

Step 3. Decide whether to count Social Security.

The closer you are to retirement, the more comfortably you can depend on receiving the current range of benefits.

So Boomers, especially Early Boomers, you're golden. Count it.

If you're in Generation X and or Y you shouldn't include Social Security in your planning.

We can estimate your benefits based on current laws and rules. But since the Social Security Trust Fund is expected to run out of money in 2040, we suspect those rules will be changed before you qualify for a check.

That doesn't mean you'll get nothing. It just means it's hard to predict what your benefits will be when you aren't going to retire for another 30, 40 or 50 years.

Step 4. Calculate how much you'll need to save.

Now it's time to let your computer do most of the work.

Go to our retirement plan calculator and enter all the information it asks for.

The only tricky part is where it asks "percent of income at retirement."

If you're a Boomer with a pension enter the percent of your income you need to replace with Social Security and savings. (That was 57% in the example we used in Step 2.)

Everyone else enter 85%.

If you're a Boomer, check the box to include Social Security.

Everyone else leave it blank.

Hit "Calculate" and the computer will tell you how much you'll need to have saved by the time you retire and how much you must save each month between now and then to reach that goal.

Click on "Report" to see how much you'll need to withdraw from your savings each year after you retire to reach 85% or your pre-retirement income.

Step 4: Sign up for a retirement plan.

Maybe you can't afford to save as much as the calculator says you should. But you can start saving with as little as 1% of your income.

The easiest and smartest way to do that is through your employer's 401(k) plan. Our 7 simple rules for a successful 401(k) can help you get enrolled, boost your contributions, invest wisely and make the most of your retirement savings over the years.

They're surprisingly easy to understand: A percentage of your income is withheld from your paycheck and deposited in your retirement account. That money is invested in stocks and bonds -- usually through mutual funds. You pay no taxes on what you save or earn from your investments until you begin withdrawing money from your account.

Our pointers can help you get started, boost your contributions, invest wisely and make the most of your retirement savings over the years.

If a 401(k) plan isn't available where you work, an individual retirement account or IRA is the next best thing.

You can open an IRA without your employer's help and save up to $5,000 a year in everything from CDs to stocks. As with a 401(k) plan, your savings grow tax-free at least until you retire. With the best type of IRA, you never have to pay taxes on your earnings.

Our 6 simple rules for a successful IRA will help you make all the right decisions.

Just look at how school teacher Kim Gray is saving for her future with an IRA. You can do it, too.

Step 5. Reassess your retirement savings annually.

Revisiting this process every year is a good way to track your progress and obtain fresh estimates based on how much your salary and savings have actually grown.

By Darci Smith

Interest.com Contributing Editor

Have a question about your finances? Ask us at editors@interest.com