How to properly dispose of an American flag
Seek local resources
Contact your local veteran services groups such as the VFW, American Legion Post, or D.A.V. to ask about dropping off your flag. Some of these groups will hold an annual flag retirement ceremony as a community service.
Burn safely and respectfully
You may burn a flag to retire it. The flag should be burned completely and the ashes buried. To add the appropriate respect, the VFW recommends all those present come to attention, salute the flag, and recite the Pledge of Allegiance before observing a brief moment of silence.
Be aware, however, that burning is best for cotton flags. Nylon or polyester flags give off fumes when burned, and these can be hazardous to both observers and the environment.
Cut and bury
The Boy Scouts of America recommends a procedure to cut the flag (never through the blue star field). When that is done, the flag ceases to be a flag and can be disposed of in any proper manner. Other resources suggest burying the flag as a respectful disposal method.
Send off for recycling
You also may send your flag to a recycling group such as Flag Keepers or American Flags Express. This is a safer alternative to burning flags made of synthetic materials. Notably, Flag Keepers also accepts state flags as well as those from friendly foreign governments.
For more information, see The United States Flag: Federal Law Relating to Display and Associated Questions.