first press the first switch and leave it for 5 mins then turn off that switch and turn on another switch for 2 mins and switch off that one also now finally switch on the third one and enter in to the room.

the lighting bulb is the third one and remaining 2 is:

Touch the bulb,  the bulb which has high heat is 2nd switch  one and which has less heat is the first switch.

i think i m correct .