Performing Your Overclock
Boot your computer into the BIOS. This can be accomplished by holding down a key (usually DEL) as the commputer boots. If your motherboard supports adjustments of the FSB, RAM, CPU, and etc, there should be a specific category in your BIOS which lists these options. Different motherboard companies use different names, so you'll need to consult your motherboard's manual, or simply explore your BIOS until you find the proper area.
Once you have come to the part of your BIOS that allows for overclocking, you should reduce the speed of your RAM, relative to the FSB. The easiest way to do this is, if your BIOS has this option, is to run the memory unlinked from the FSB. If your BIOS dosen't provide for this, you'll have to turn down the System Memory Multiplier. It is possible that your motherboard will list the same function differently; check your manual for details.
If you can run your RAM unlinked, you'll want to set the RAM to the speed at which you usually run it (if you don't know and can't find out from documentation it is usually listed on a sticker on the RAM itself). If you have to keep a multiplier, set it as low as possible. In my case, I had RAM that typically runs at 800Mhz. I set it down to 667Mhz, the lowest my motherboard would allow. As your increase the speed of your FSB, the RAM's speed will also begin to increase. Setting the memory multiplier low will help ensure that you're only worrying about overclocking your CPU, and not dragging your RAM along for the ride.
Having isolated the RAM, you are now going to change the speed of your FSB. Most likely, it is set to "Auto", or there is a frequency control option which is set as "Disabled". This is because your motherboard has been automatically determining how quick the FSB needs to be. Turn off the automatic control, and you should find a field with a number in it followed by Mhz. This will be titled CPU Host Frequency or similar.
Selecting this field will allow you to input the Mhz you want the FSB to run at. Remember, the frequency of the processor is determined also by a multiplier. If the multiplier is 9x, then increasing the FSB frequency by 10Mhz will increase your processor's frequency by 90Mhz. You want to start small. Increase the FSB by 5mhz. Save the settings in your BIOS, and reboot. Allow the computer to boot to your operating system.
Congratulations. You've performed your first overclock.