Once you have removed the old thermal paste, it's time to apply the new paste. This model has a hole in the heatsink so it does not need thermal paste applied on the smaller pad.

Do not use too much thermal paste, just enough to cover the bigger portion of the pad. If you have a spreader, use it. The thermal paste will apply evenly after you tighten the heatsink.

Put the heatsink back carefully and tighten the screws in order 1, 3, 2, 4 to ensure even pressure. Don't forget to plug in the fan cable again.