Step 2: Determine where you want to put your amplifiers.
Don't forget if you have some serious subwoofers you may need a capacitor to offset them dimming your headlights during heavy hits.
Always remember if you amplifier is in a tight space, install a fan for ventilation (computer fans work well)
Attach to the back of the subwoofer box
Underneath the driver/passenger seat
Behind the dashboard (smaller amps)
Underneath the trunk near the spare
After you figure out where you want to install you amplifier. Go ahead and put it in this location, test the feel and fit. Install it so that when your get your wires to it, it will be ready.