hello i think if you want to change the battery you could but if you phone has that circle at the bottom of it so when you click it it turns on your phone press and hold that button and press and hold the turn of putton at the same time. If you do not have i press and hold the turn of button and press and hold the volume up button.
Power off your iPhone. If you're using cotton, place a toothpick on the cotton and twist until it catches and starts to wrap around the toothpick (Only use a small amount). Holding your iPhone so the backside is facing up, place the toothpick inside the chargin port. Scrape against the back wall of the port