Hooking up home speakers in your car is only necessary if you are including audio devices you want inside that won't connect to the main stereo, such as an MP3 player or CD player, if the car doesn't have one. You won't get good sound out of home speakers wired to the car stereo because the stereo won't produce enough amps. Hooking up home speakers is a matter of finding the right place for them and connecting them with standard stereo cables to your auxiliary devices.
Pick a location to mount the speakers. If they are small enough, you can secure them to the top of the dashboard with adhesive strips as long as they don't block anything like the airbags. Other places can include the back seats (if you don't have many passengers) or floorboards with Velcro strips.
Install the music player(s) in the car. The top of the dashboard is your best location here. If you're including something larger like a home CD player, store it under a seat and make sure it has a remote control.
Connect the players and speakers. This will usually require mini-coaxial cables that have the single thin plugs with two black bands across them, If you are hooking up more than one speaker, you will need a coaxial splitter cable. In some cases, you'll need full RCA cables with the red and white plugs.
Tuck the cables away where they won't get in the way of anything else within the car. Run them along the side edges of the trim and against the bottom edge of the windshield. You can secure them down with electrical tape or something similar.
Make sure there is power to the speakers (and the devices they are connected to). If they were designed as portable devices, they can use batteries. Otherwise, get a cigarette lighter adapter that has the exact type of voltage connector for them.
