Remove the screen.

If you replaced your screen, check the front-facing camera hole and the sensor cutout on your replacement screen, and remove any remaining liners.

Check the frame for deformed grounding springs that stick straight up. These spring contacts should rise at a shallow angle. Use your finger to gently bend any deformed springs downward.

Follow this guide if you're using custom-cut adhesives for your device. Follow this guide in case you're using a pre-cut adhesive card.

If you're installing a new screen, follow this guide to calibrate the fingerprint sensor.