Connect any XLR microphones to the corresponding black XLR jacks on the mixing board. Your XLR jacks have three slots in a triangular formation. If you're using condenser microphones, you will need to use Phantom power. If your mixing board contains a Phantom switch (as most do, usually along the back), flip it to the "On" position. Look for the words "Phantom 48v."
Connect instruments like guitars, bass guitars and keyboards to the corresponding 1/4-inch audio ports on the mixing board, using TRS cables. When connecting an instrument, do not use the same channel strip already containing a microphone, as each audio input needs its own strip on the console. This enables you to manipulate every audio source precisely.
Connect digital MIDI sources to your mixing board. Not all mixing consoles are MIDI compatible, but some allow you to connect your digital instrumentation, such as synthesizers, drum machines and sequencers, for MIDI control. Connect a standard MIDI cable to the "MIDI Out" jack on your MIDI instrument and to the "MIDI In" port on your mixing board to transmit from the instrument to the console.
Connect any RCA devices, such as samplers, turntables, tape decks or other sources, to the corresponding red and white RCA jacks. RCA connections can come in handy if you're using sound effects or backing tracks during a live performance or recording, or for performing a live DJ set.
Create effects for your mix using the Aux-Send and Aux-Return jacks. For instance, if you have an effects processor and would like to apply a reverb effect to your mix, connect a 1/4-inch audio cable to any "Aux-Send" jack on your mixing board and connect the other end to the "Input" or "Line-In" on your processor. Then connect a second cable to the "Line-Out" on your processor and to the "Aux-Return" on your mixing board.
Connect your mixing board to a second source. Mixing boards alone are capable only of receiving and transmitting sound waves (and in some cases MIDI notation). For recording or mixing, you will need extra hardware. For a simple live setup, connect amplifiers or speakers to the 1/4-inch "Output" or "Line-Out" jacks on your mixing board. For more intricate live performance, connect your mixing board to a stage box, using the "Output" jacks on the mixing board (L-R, for stereo) and the "Line-In" jacks on the stage box. Connect additional speakers and amps to the stage box. If you're using a USB mixer for recording, connect the USB cable to your PC.