The first instinct for many people for whom retirement is on the horizon is to relax. After all, isn't that what retirement is all about? You've worked your entire adult life to relax throughout your golden years!

But retirement is not without its challenges, whether you’re retiring early or late. And those who don't come up with a retirement plan could find it particularly difficult. Investing for retirement is essential because the bills don't stop coming once you stop working. In fact, they often increase: it is estimated that a couple that retires at age 65 will spend $160,000 in health care the remainder of their lives. Most alarmingly, that figure does not include any costs incurred by long-term care such as a nursing home.

Saving for retirement is a must for those who want to make the post-working years as enjoyable as possible. Here are some tips to keep in mind as you begin formulating your retirement plan:

—Try to save 20 percent of your annual income. This is difficult, especially for those who are paying for children to attend college. But if you can set aside this amount and place it into a bank account and allow it to collect interest, you'll have a nice foundation for your retirement plan by the time you actually retire.

—Max out the contributions to your 401(k), IRA and Roth IRA accounts. Those younger than 50 can contribute up to $16,500 each year to their 401(k) and $5,000 to an IRA. Those older than 50 can chip in as much as $22,000 to their 401(k) and $6,000 to an IRA. Do the math—that's a great way of saving for retirement!

—Invest in bonds. A good retirement plan is one in which 70 or more percent of an investment portfolio is tied up in bonds. Most bonds pay semiannual interest, which in turn creates a consistent income stream for retirees. Because of their very low default rates, municipal bonds issued by states and cities are the most reliable bonds in which to invest. A state bond hasn't defaulted since the Great Depression while more than half of the municipal bonds to default from 1920 through 2010 did so during the Depression.

• Since tax sheltered accounts such as IRAs do not require you to pay taxes on the interest in the accounts until you withdraw the funds, a great option is taxable municipal bonds. Taxable Municipal bonds give you the safety of a municipal but the yield of a taxable entity. For most people when they do eventually take out the funds from their tax sheltered accounts, they are retired and in a lower tax bracket which makes their interest taxed at a much lower rate.

—The stock market has understandably scared off investors of all ages since it collapsed in 2008, but those who have the ability to invest in blue-chip stocks should do so as part of saving for retirement. Hanging on to such stocks for an extensive period of time provides security as well as, eventually, the opportunity to sell at a profit.

—Know that it is never too early nor too late to embark upon a retirement plan. Obviously, the younger you start, the better off you'll be in the long run. But those who are in their 50s or beyond shouldn't be intimidated by the size of the task ahead of them. Money is lost every single day someone puts off retirement planning. Ponder these tips and get in touch with your investment advisor today!