Warning: The Copper IHS for 6th to 8th Gen Intel CPU's LGA 1151 will NOT work on the 9th Gen CPU. The 9th Gen CPU die is much thicker and using this Copper IHS will cause excessive pressure on your CPU, motherboard and socket once the motherboard clam is closed.
Detailed steps on how to prepare, De-Lid and Re-Lid your Intel™ CPU are outlined below. You can also go straight to a couple of great YouTube™ tutorials. The first courtesy of Tewan demonstrates the end-to-end process using the Rockit 88. The second by fraknu shows how it's done in detail with the Rockit 99.