It's pretty easy bro, easier than rooting an iphone lol.
You will need to learn how to take apart your old stereo without breaking anything. I suggest you get yourself a trim tool kit. It's a pry tool for un-clipping the plastic panels. I got one from Walmart for 15 bucks but you can buy it cheaper on ebay. Next, find all the screws that you'll need to unfasten, some are hidden, so be gentle and patient when you are unscrewing everything. Don't get frustrated and start yanking stuff out.
When all the are panels out, taking out the stereo sometimes require a special tool, I don't know what its called but its two thin pieces of metal rods that you insert on the outer edges of the stereo (for aftermarket stereo), this releases the latch and allows you to pull the unit out. This is not always the case. The tools usually comes with the stereo.
The fun part is the wiring. There's like 10 wires you have to worry about; power, antenna, speakers wires, RCA wires, a few others. The black wire is always negative, red for positive. If you are switching from OEM to aftermarket, most likely you will need a wiring kit for the new unit, unless you're prepare to cut and splice it yourself. It's a last resort and I don't recommend it.
Car stereo installation is easy but time consuming. Adding an amp and sub requires more work, I suggest you do it separately. I forget to mention, before you do anything, you might want to disconnect the battery cable from the terminals to prevent fuses being blown, depending on how the power wire is routed, you could be dealing with a live power wire and that's not a good thing.
