What is the best and simplest way to put in subs and an amp without dimming lights and my battery dying, etc?

I know that a capacitor stores unused energy if I remember right, but I'm not sure on that. I know that I could add a second battery, but I'm not sure how great that would work mounting it and on my alternator. Please help! Any info would be great! By the way, I have two Audiobahn 10" subs in a sealed, ported box with blue neons around the speakers. And the amp is a two channel 800 watt Lanzar Vector. Lastly, I drive a 1989 Ford Bronco.

Depends on you. An amp draws more as you turn it up, if you leave it at a reasonable volume you won't have a problem if thats all the system you have. If you tend to blast it constantly at max and especially if you add onto the system with more amps ect you'll likely want an upgraded alternator with higher output, the cap, large wires throughout ect. Just keep one thing in mind, cycling a battery or it constantly running low is what kills them rather quickly. You need to do whatever it takes so the battery isn't taxed low all the time…