You need to run a power wire from the battery. a set of RCA jacks from the deck, and a "turn on " wire form either the deck, or a source that will come on when the ignition is turned. Then of course connect the amp to the sub's. Wire thickness for the power wire is anywhere from 8 to 0 gauge. If you tell me what amp i can tell you what gauge wire you need, expect nothing inder 8 gauge. Run the RCA's down one side of the car, and the power down the other. Be SURE to ground the amp to a SOLID peice of the car, something that will be in contact with the whole frame. Bad grounds = bad sound, poor power etc.
Zack