Just take your time. Are you removing the mobo? make sure theres room around the cpu.Its socket A isnt it,so you will need a flat screwdriver the clip will have a slot for this make sure you use one that fits snug.This will mean the screwdriver cant slip and hit the mobo.
Do not be surprised by the amount of force you need. when you refit cpu it should just drop in no force needed,gently press down on cpu when you press retaining lever down to ensure a good connection ,then replace heatsink very carefully again using more force than you may expect .
Good luck. I remember my first time
fiddling around in the dark,then the force you need to fit it.Ive done 100 never yet damaged a core and if i can do it you can m8