Very simple
Run power wire from positive with a fuse block within about 10-12 inches from the battery. How much rms is your amp pushing not peak? The bigger the wire the safer you are. You can buy cheap kits at walmart that are more than sufficient for the entry level person. Just dont use a compacitor, they are useless and can be dangerous. An extra battery in trunk the the correct way if you need more juice. If you running say 400-600 rms run a 2-6 gauge, ide say go all out and just get 0 but your gonna need a distribution block to drop the wire to a gauge that can fit your amp and they are kind of pricey. Ok now that you have wire run from your battery to your trunk your going to want to run a remote and rcas. Run your remote and rcas down the other side of your car because the power from your power cable have been know to cause interruption.Hook your remote wire ( only need to be like 18-22 gauge btw) from your interior lights or your sunroof so that when the car is on your remote is on.
And obviously your rcas are hooked up to the back of your deck. Now that that is all said and done all you need now is a good ground. You can probly get away with just puching a hole in any metal in your trunk and scraping the paint away and wrapping a, again 2-6 gauge wire around a sheet metal screw and putting it in there. But the correct way to go about it is to use a grounding block so you have more surface of ground and a much more solid connection. If your wondering how to wire your subs when you have everything hooked up for the most punch and stability there is this great site.
http://knowledge.sonicelectronix.com...woofer-wiring/
Once your all wired and ready to go there are correct ways to go about tuning in your amp and subs so that you can get the most punch and do it safely. Honestly though for your first install just turn everything down on amp. Then put your radio on to a good song and blast it to max volume without distorting your speakers. Now tuen up your gain untill your subs start distorting then turn down a slight bit (usually about 3/4). Do not use bass boost as a method to get more bass unless your amp is maxxed out and your subs can handle a **** load more.
lmk if you need anymore help