Apply thermal paste onto the main chip or on the connection side of the fan.

Place the heat-sink over the GPU carefully, lining up any screws or clips.

Apply heatsink on thermal pads as applicable.

Use only a small amount of heatsink and spread evenly using a card, or apply pressure evenly when connecting components.

If there is thermal tape or pads that were removed for the reflow, place these back in their original position.