If your iPhone has a physical SIM tray, eject it before you proceed.

Make sure all the connectors are disconnected from the top of the logic board.

Insert the flat edge of an opening pick between the battery and the left edge of the logic board. Hold the pick in place with your fingers.

Insert the flat end of a spudger underneath the right edge of the logic board.

Gently pry with the spudger to lift the logic board and disconnect the display connector.

Don't remove the logic board yet. There's still a cable connected to the bottom side.