ok the diagram is in spanish but what the heck.... it's got pics!!!
.. i'll try to explain it though:
since you want to activate them with a switch, you'll use the bottom coloured diagram...
if you're gonna use the stock fog switch the 2 pins i used are the bottom row ones, closest to the steering wheel.. on the left... check them thought, i got the signal from the fuse kick panel... a fuse that had 12v on ignition ON position..
hope i made myself clear, any questions i'm here to help!!