all you need to do is take a 12v feed direct off the battery with a decent gauge wire (cant tell you the size off the top of my head) with an in line fuse of (cant remember that rating either lol) and take it to the back of the car, where in the spare wheel well there is a red/black wire which is your ignition feed. You need to connect this to a new relay of about 20A rating i think and then make an earth to complete the circuit. Pretty simple really, but by the time youve sourced the relay, crimps, wire, heatshrink you might as well save some time and spend another 15-20 quid and buy one thats ready to fit with instructions. HTH