This mite take a while :
Flip the first switch on and make sure two and three is off and wait 5 or so mins, then turn it off. Turn on the second switch, and have 1 and 3 off. Enter the room now - if the bulb is on, no 2 is the right switch. If it is off, touch the bulb - if it is warm then it was switch 1, if not warm then it will be switch 3.



