For many of us, retirement is far in the future, and today's bills seem more pressing. But it is very difficult to make up for the lost years if you delay beginning your retirement savings.

For many workers, 401(k) plans are the easiest way to begin a retirement savings plan. As soon as you become eligible, you should begin making contributions. This money will come out of your paychecks before you even see it. The money will not be taxed now, so your taxable income will go down for the current year if you make 401(k) contributions. Instead, you pay taxes on the money when you withdraw it during retirement.

So, how much should you contribute? Many financial pundits will tell you that it's imperative for you to contribute at least 10% of your salary. If you can manage to start out at 10%, that's a great beginning. Others will say that you should contribute the maximum allowable to your 401(k) plan ($15,500 in 2007). This advice may be good, but it may also be unrealistic.

The truth is that the right contribution levels for you will depend on your individual circumstances. If you are somewhat late in starting to save for retirement, you will need to contribute more. If you are relatively young, and plan to contribute consistently during your working life, your contributions will not have to be as large. If you are working to pay off a large amount of consumer debt, it may be better to keep your 401(k) contributions relatively low until the high-interest debt is reduced.

If making contributions at all seems out of reach, call your 401(k) plan administrator or Human Resources department and find out how much you must contribute at a minimum in order to participate. Start with the smallest contribution, and when you get a raise, increase your 401(k) contributions by a percentage point or two. In this way, you can work up to a contribution level that fits your financial plan.

If at all possible, you should contribute enough to get your employer's match. Some employers contribute to 401(k) plans ONLY if workers also contribute. If your employer matches your contributions up to 5%, for example, you will need to contribute 5% in order to get the full 5% contribution from your employer. Even before you have invested the money, the employer's contribution in this example means that you will have doubled your money.

Once you have set your contribution limits, you will need to choose investment vehicles. Many 401(k) plans offer a variety of mutual funds, which allow you to own shares of many different stocks. If you are an inexperienced investor, you may want to see if your 401(k) plan offers what's called a target-date retirement fund. In this kind of fund, the fund manager changes the risk levels over time as you get closer to retirement. You choose the fund based on the year when you expect to reach full retirement age.

It is not always appropriate to invest in a 401(k) plan (although it will likely make sense in most situations, especially if there is matching of contributions by the employer). If your employer doesn't match your contributions, you need to look carefully at the investment options in the plan. In some cases, if the mutual funds available have high costs or don't meet your investing style, you may be better off investing in an IRA or some other retirement savings vehicle.

No matter how much you invest in a 401(k) plan, you should not withdraw the money until you reach retirement age. If you change employers and want to take your savings with you, roll it into your new employer's retirement plan or into an IRA. It is almost never in your best interest to withdraw the money early.