Technical Punto mk2 rear speakers help!

[mannionmax]

Hi, I am trying to install some 6x9 speakers to my parcel shelf. My punto does not have rear speakers as standard i.e. no wiring to headunit. I was wondering is there any guides on how to a) run speaker cable through the car to the headunit and b) how do you wire in the cable to the headunit?

Any help would be much appreciated!!!