Locate the computer’s one-eighth inch microphone jack. The jack will be located on the front or the back of the computer, and is typically placed by the speaker jack.
Plug in one end of the cable to the microphone jack, using the one-eighth inch connection.
Connect the other end of the cable to the mixing board’s input jack. Depending on the board, the input will be either a quarter-inch jack or an XLR jack. However, you may choose to use an RCA input and send the computer’s signal through the “Tape In” input. Once the signal is sent to the mixing board from the computer, it's level and equalization may be controlled using the channel fader.
Locate the computer’s one-eighth inch headphone jack and plug the cable in. The jack will be located either on the front or the back of the computer, and often will be beside the microphone jack.
Plug the other end of the cable into the mixing board's output jack. The output jack is typically a one-quarter inch input, so you will need to use a one-quarter inch to one-eighth inch cable.
Right-click on the speaker icon beside the clock on the Taskbar and select “Recording Devices." Place a check mark beside the box label indicating that you would like to hear the signal through the microphone input. Your mixer is now connected to your computer.