Just like Wayne said you'll need an some kind of amplifier. For a main living space with multiple speakers you'll want an AVR that will do both digital sources and surround decoding for the multiple speakers. What AVR depends greatly on your budget, number of speakers and features that you want.
Once you have the AVR you'll want to hook the wires up to the correct port/output on the AVR. If you have a wallplate this could be a simple piece of speaker wire to jumper from the AVR to the wallplate. After the speakers are connects you should run the auto-setup feature of the AVR and you should be done.