Step 1 Power down your iPhone 6s

Step 2Remove the two bottom 3.4 mm Pentalobe screws located next to the lightning connector. 

Step 3Place a suction cup near the home button and pull the display assembly away from the rear case. Use the iSesamo opening tool to slice through the adhesive and help carefully separate the display assembly from the rear case.

Take your time and apply firm, constant force. The display assembly is a much tighter fit than most devices and is held down with adhesive. 

Do not open the display assembly more than 90 degrees, as it is still connected at the top by three ribbon cables that may break if stretched.

Step 4Remove the following 5 Phillips screws securing the metal cover to the motherboard. Now use the fine tip curved tweezers to disconnect the LCD, digitizer and front camera and proximity sensor cables. 

Step 5Remove the following 2 Phillips screws securing the metal battery connector bracket to the motherboard. Now use the fine tip curved tweezers to remove the metal battery connector bracket and then disconnect the battery connector from the motherboard.

Step 6Use the fine tip curved tweezers to peel up the edges of the three adhesive strips at the  bottom of the battery. Grab the end of the first adhesive strip and try to keep the strip flat and wide. 

Slowly and gently pull each strip up and away from the iPhone. The strips will stretch to many times the length of the battery- keep pulling until they come out from between the battery and the rear case. 

Now, remove the battery from the rear case of the iPhone 6s.