Remove the screen from the phone.

If you replaced the screen, check the screen's front-facing camera hole and remove any protective liners covering it.

If you are using a custom-cut adhesive, follow this guide to correctly apply new screen adhesive.

If you are using Tesa tape to reattach the screen, follow this guide.

During the boot-up process after reassembly, the screen will go through a calibration sequence. Do not touch the screen during this process, as it could result in improper touch calibration and create touch issues.