Generally, headphones are connected directly to an audio device for the purpose of personal listening. If you want to listen to your audio device but do not want to be limited by the length of your headphone wire, you can make use of a simple converter to turn your wired headphones into wireless ones.
Connect the wireless headphone transmitter to the headphone port on your audio device. Extend the antenna on the transmitter to its full length.
Connect your headphones to the headphone port on your wireless receiver. The receiver is small enough to fit in your pocket.
Turn on your receiver, transmitter and audio device. Put on your headphones, and you should be able to hear the signal from your audio device on the headphones.