October 3 might find you fondly looking back at the 1955 TV debuts of Captain Kangaroo and The Mickey Mouse Club or perhaps watching the 2007 Major League Baseball playoffs (our sympathies, Mets and Padres fans).

Since October 3 is also national Change a Light Day, one other item on your agenda that day should be to replace at least one incandescent bulb in your home with an Energy Star-qualified compact fluorescent light (CFL). As we reported in “New twists in savings,” you can save significant energy and money by using CFLs. In fact, according to the U.S. Department of Energy, if every American household were to replace one incandescent bulb with an Energy Star CFL, enough energy would be saved to light more than three million homes for a year and cut annual energy costs by $600 million.

We recommend you buy only Energy Star bulbs. Keep these other tips in mind when shopping for CFLs:

Match the bulb to the task. Generally, spiral fluorescent bulbs are ideal in lamps, pendants, and wall sconces. For recessed fixtures, use flood CFLs; they cast light evenly on the task area. You can use globes in vanity strips, say over bathroom sinks, or in hanging pendant lamps. And if you don't like the twisted look of some CFLs, use a covered type; these do, however, take longer to come to full brightness. Some CFLs even have three brightness settings, and others can be used with dimmers.

Look at the lumens. The wattage of a bulb tells you how much energy a bulb uses; its lumens measurement indicates the amount of light it provides. Check the packaging to find a CFL that delivers as many lumens as the bulb it's replacing and uses the fewest watts.

Choose the color. Energy Star CFLs labeled "soft white" or "warm white" are designed to match the light of a typical soft white bulb. Those labeled "bright white," "daylight," or "natural" have a cooler blue color, comparable to a bright white incandescent.—Kimberly Janeway

Essential information: Learn 10 easy way to cut consumption in “Save hundreds on energy costs.” Also read our latest reports on thermostats, windows, and space heaters.