I'll need to do this tommorw or tuesday when I get my new CPU/fan.
I'l just touch the radiator though to earth me most likely, as thats another okay method I believe to get rid of built up static.
I'd then take off the old heatsink/fan by taking off the brackets and then turning while pulling.
You don't want to pull straight off, since the bond with the heatsink/cpu can be quite great, so twisting while pulling makes sure it slides off.
Then I'll probably get a tissue or something and wipe the processor. I wo't bother using any special liquids, etc, since the last time I took the heatsink off, it wiped off really easily, leaving no residue anyway.