It is something very easy, when you take the player, in the connector of it you will get 4 cables .. 2 purple color and 2 green color ..
Every two colors are an audio output. that is to say each output for a speaker ..
the speakers bring approximately 2.5 meters of cable this will be enough, you must bridge negative and positive cables with positive.
How will you recognize which one? FACILL !!!! The negative cable is distinguished because it has a fine black line is to say; The negative cable of the speakers will have a black stripe this also applies to the cable is audio outsides.
This cable should be traveled from the central panel to the rear of the car? how ????
In the doors of the doors you must have plastic parts, this is going to detach it very carefully and there you will travel the wiring ..