Connect the other end of the two jacks to the "Input" jacks on the amplifier.
Connect your input devices. If using microphones, connect them with an XLR cable to the "XLR In" jack. If using electric guitar or bass, use 1/4-inch jack balanced instrument cables. If you are connecting a CD player, use a phono cable and connect it to the phono jack.
Turn the "Main Mix" fader to zero and turn on the Behringer 802. Minimizing the fader level protects your ears from any expected sounds. For example, if a loose cable causes a buzz, the mixer won't send a signal to the amp while the "Main Mix" fader is on zero.
Set the "Master Mix" level to approximately "2." It's preferable to use a low sound setting when adjusting levels in case you make any errors that cause feedback.
Turn on the Behringer 802. The power switch is located on the rear of the unit.
Turn on the amplifier. Doing this means the sounds going into the mixer will be projected from the speakers to which the amp is connected.
Adjust the "Level" dial on each channel while auditioning the input signal. For example, when adjusting the level for the channel to which the microphone is connected, sing into the microphone. The "Level" dial governs the gain. If the red warning light starts flashing, reduce the gain.
Adjust the "Master Mix" level to your preference. This governs the entire output of the Behringer 802 mixer, rather than the output of each channel. Regardless of volume, the gain differences between each channel will remain the same.