I'm on a different BIOS so I'll have to be a little general here:
First Step is to be able to monitor the temperature of your CPU. (probably a utility came with your MoBo, otherwise download Motherboard Monitor or some other app.)
Second step is to search around and find out how hot your CPU should be allowed to get. (temperature is everything... the cooler it is, the easier it will OC, and also if it gets too hot..... well thats bad.)
Third step is to go to the BIOS setup screen and raise the Front Side Bus (FSB) frequency a couple MHz. ("FSB" = "System Bus")
Save the settings and boot into windows.... If windows will not boot, your CPU temperature gets too high, or you see instabilities in system operation, you have raised FSB too far and need to return to BIOS and lower FSB a bit and then try to boot again.
Instabilities due to excessive OC may not occur immediately, you need to run some apps. that heavily load your CPU for a while to be confident you are stable.
Once you have taken FSB as far as you can (stabily) you can opt to raise the CPU voltage ("Vcore") a LITTLE bit. This is where your heat is going to come from.... watch CPU temperature carefully. turn off your computer IMMEDIATELY and then go to BIOS and lower Vcore if temperature is getting too high.
So now you have elevated Vcore SLIGHTLY; repeat the FSB procedure (It should let you go a little higher now)
lather, rinse, repeat!
I only do moderate OC on my machines. If I see ANY instabilities, I back off FSB at least a couple MHz to keep it stable (I can't stand crashes)
Hope this helps! (I'm not the most experienced overclocker, so get advise from others... don't only take my word for it!)