When an incandescent or compact fluorescent light bulb burns out, the simple thing to do is throw it into the trash without a second thought. Although it's not such a big deal -- from an environmental standpoint -- when you toss an incandescent bulb, a broken CFL can be a dangerous thing because of the mercury that it releases once broken. It's important to take precautions when disposing of any type of light bulb due to the dangers of shattered glass or mercury release.
Grip the light bulb as close to its base as possible to avoid breakage, and turn it (anticlockwise (counterclockwise) to loosen it.
Wrap the used bulb in old newspaper or some other material that will help keep the bulb from shattering and making a mess.
Place the wrapped bulb in the wastebasket for disposal.
Contact your local municipal solid waste agency, and ask whether it's permissible to put broken or used CFLs into the trash for pickup. Some agencies don't allow this option and only recycle.
Place the CFL into a plastic bag with a seal or a small plastic grocery or garbage bag. Ensure that all excess air is removed from the bag, and seal or tie it closed.
Place the sealed or tied bag into another plastic bag, and seal or tie it closed. The CFL is now double-bagged.
Place the bags into the waste receptacle for pickup.
Local retailers in your area, such as a hardware store, may accept CFLs for recycling. Some light bulb manufacturers offer mail-back services that allow you to package and mail in your used CFLs for recycling.