a single gang two way switch is wired thus,live feed from the ceiling rose loop in,is run to the common on the first switch,then you run wire from l1 on first switch,to l1 on second switch,then you run wire from l2 on first switch to l2 on second switch,then you run wire from the common on second switch to the flexi cable on ceiling rose,(that the brown or red cable that the bulb holder is connected too)now you have it,a 3 gang is wired same way,cept you loop the live supply from common to common
mm, September 2011