Do you want to "drop it off", or retire it yourself.
For drop it off, call VFW or American Legion Posts.
To do it yourself, basically it just boils down to do it respectfully.
Use a grill over the fire. This keeps the flag off the ground, and keeps it from smothering the fire.
You can look online, there are various ceremonies you can do.
At my Legion Post, we dismantle the first flag and recite from a script on each stripe.
Then, we have hours of retiring, we have so many.
Not all flags should be burned. Google nylon flag burning.
The American flag is the symbol of patriotism in the U.S. In the past, American flags were made out of wool and cotton. Burning old cotton and wool flags is not considered a hazard to the environment. Today the majority of American flags are made of nylon. Burning nylon is very hazardous to the environment and dangerous to one's health. Disposing of nylon American flags can be done in a less hazardous way.
Check into your local flag recycling programs. All worn nylon American flags do not have to be burned. In fact recycling your tattered nylon American flag can help create new nylon American flags and save the environment in the process.
There's a funeral home in Crown Point that will put them in with a veteran who is being cremated. I been meaning to drop a couple of flags off with them.