Set your heat gun to the lowest setting(around 150 degrees)

If you are missing lines on the screen, aim at the top ribbon cables and heat the cable evenly for about 5 seconds.

Then heat and apply pressure using the plastic opening tool for about 5-10 seconds, applying pressure to different sections of the ribbon cable within that timeframe.

Continue to apply pressure throughout the ribbons.

If the screen is Glitchy, do the same for the bottom ribbon cable.