Simple and easy it depends alot on ur motherboard. Just enter bios and make sure you enter advanced mode so it will show it. You should be able to overlock the graphics, fsb, processor and ram.
Overlocking the FSB basically overclocks everything on ur board. But is the easiest and most dangerous.
Overlocking the processor is easy aswell but may require the fsb to overlock some for stablity. Overclocking these will cause automatic reboots.
Graphics and ram tend to be harder cause if you overlock them too far than you system wont reboot or turn on and you have to reset the entire bios and do the thing over again. Not only that but it will damage your video card. IOr it will simply freeze up when in windows like every 5 secs you will get a 1 sec lockup and there will be alot of artifacts like black lines. It will also mess up the plug and play of the card and when that happens it also affects your lcd's ( i know this
) This is why I will not overclock that much, maybe the processor but nothing else.
Overlocking the processor is the least dangerous while the graphics card is alot more dangerous and more easy to destroy by overclocking.