A 5.1 speaker system must be connected to a source equipped to handle the system, such as a home theatre receiver or amplifier. Most of the speakers in a 5.1 system are connected to the receiver with speaker wire, with the exception of the subwoofer, which is connected with a special cable.
Place the speakers in your 5.1 speaker system in the locations you'll be using. For the "5" speakers -- centre, two fronts, and two surrounds -- cut lengths of speaker wire long enough to reach from the speakers to the back panel of the receiver. Consider how you'll be routing the speaker wire, and make the wires are cut slightly longer than you need in case you need to reposition the speakers.
Strip the insulation from the ends of each speaker wire, so that each speaker wire's positive and negative leads have about 1/2 inch of bare wire exposed. Usually, the wire with the brown or copper-coloured insulation is considered the positive, and the wire with grey or clear insulation is considered the negative.
Connect the speakers to the receiver, one at a time, following this method:
Loosen the terminals on the back of the speaker and insert the bare ends of the wire leads. Put the positive lead into the positive terminal (coloured red), and the negative lead into the negative terminal (coloured black). Take the other end of the wire and connect it to the appropriate output on the receiver. The speaker outputs of the receiver will be marked "Speakers - location (ie, centre, right front, etc)." Loosen the appropriate terminal, slide the wire into it, and tighten down. Again, put the positive lead into the positive terminal and the negative into the negative terminal.
Take your subwoofer cable and connect it to the "Sub Out" jack on the receiver. The subwoofer cable consists of an insulated cable with RCA plugs on each side, so connection is a simple matter of pushing the plug into the jacks on both the receiver and the speaker. Connect the other end of the cable to the subwoofer's sub cable jack. Plug the subwoofer into a wall socket for power.
Test your speaker system to make sure all of the speakers work properly. If you left a lot of slack in the wires to the speakers, bundle up the excess and tie them with cable ties.
If you plan to install your speakers more than ten feet from your receiver, consider buying a heavier grade of speaker wire. That will reduce signal loss and reduce the strain on your receiver.
If you plan to run speaker wire through walls, you will need a special grade of wire.