Iphone 6 and Iphone 6S has a same disassembly process.
Tools needed for iPhone 6 disassembly.
Screwdriver
suction cup
Plastic spudger or plastic card
Links to the necessary tools you can find in description
Remove two screws on the bottom
Using a hair dryer, heat the front side
Fix suction cup near "home" button
Pull up the ring of suction cup until gap appearing
and you can insert plastic card there
Slow and gently detach the display
along the entire perimeter of the iPhone
Remove two screws and disconnect the battery cable
Do not use the metal objects to remove it.
Remove four screws and disconnect the LCD connector
Do not use the metal objects to remove it
Remove three screws and disconnect the camera cable
Disconnect the iPhone 6s camera module