Program the towers you are within range of, usually your county and maybe any county within 20-25 miles of you if you want to listen to them.
If you travel to different areas of the state then you could program in the towers for that area on a quick key you can turn on/off when needed. I have all the towers of the surrounding area programmed into my scanner. When I go to Fort Worth I turn off my local towers and turn on the
Fort Worth towers.