The sound output comes through a 1/8" jack. You'll need to purchase a cord with 1/8" jack on one end and two RCA jacks on the other. Connect that to an amplifier preamp input and connect your speakers to the amp's output.

If you want to try and see if the laptop sound card can drive the speakers directly, expose the wires on your 1/8" jack cord to connect your speakers. It will have a red wire, a black wire and a shield. The red wire goes to the (+) post on your right speaker, the black one goes to the (+) post on your left speaker and the shield goes to the (-) post on both speakers.