You need to put the head set in discovery mode. Usually by holding one of the buttons for 5-10 seconds. If there is a light on it it should flash fast. Mines goes green and red fast to say it in discovery mode by holding the play button down for 5 seconds.. Some may just have one colour. Once it's I'm discovery mode switch on your bluetooth on the iPhone and it should find it. You may have to put a code in which normally is 1234 or 0000.