In 1958, the Federal Communications Commission allocated a block of frequencies in the High Frequency range for Citizens Band (CB) radio. The commercial equipment available for CB radio has been vastly improved since the late 50s, but even with the latest technology, a CB radio transmitter is only as good as its antenna. Typically, a Standing Wave Ratio (SWR) meter is used to tune the CB antenna to the optimal electrical length; however, if you do not have access to a SWR meter, you can still tune your CB antenna with success.
Locate the second CB, not the one you are tuning, at least several hundred yards away from the CB you are tuning.
Select the same channel on both CBs, the one you are tuning and the second one you are using to "tune" the antenna.
Establish communication between the two radios or between the CB you are tuning and the mobile phones.
Key the microphone on the CB you wish to tune and start talking or transmitting a steady tone.
Listening on the second CB or mobile phones, adjust the tuning screw on the antenna until you achieve the best possible signal on the second CB. This requires constant transmission of sound from the CB you are tuning, vigilant listening at the second CB and good, instant communication between the two. Assistants are incredibly helpful at this point.
This will work in the short term, but it is not ideal. SWR meters are fairly inexpensive and are the best way to tune your CB antenna.