Siwtch off pc, I ususally dont even bother removing power lead but just switch off the switch on the power supply at the back of the case. Touch the case of the PC to ground yourself, pick up stick of memory, put in slot.

That makes it sound like I have thought about it but in reality I just wade in there, done hundreds of memory upgrades in the past couple of years and not fried anything (apart from the one i managed to get in backwards which took out the motherboard in style )