You will want to do your OC'ing in BIOS. Find the settings for increasing the CPU clock multiplier. Since you have a BE processor, it will be easy and you should be able to get most of the OC with the unlocked multiplier alone. Take the multi up a single digit at a time. Reboot and check temps and stability running something like Intel Burn Test using the default settings. Watch that your core temps do not exceed 62C for any extended period of time. An occasional peak and back down is fine. If all is stable and temps are good, go back into BIOS and take the multi up another click. Repeat.
http://www.techspot.com/downloads/4965-intelburntest.html
Eventually, you will reach a point that the OC is unstable. At that point you can either back off to the last good OC and leave it there. Or you can take the vcore up a small amount at a time until the OC is stable again. After that, you can continue with the multi increases if you want, playing with the vcore as needed. But don't take the vcore over 1.5v for now. (I don't even like it that high) Depending on how old the CPU is and how many previous owners it may have had, it may be nearing its EOL. Don't hasten it.
If you are new to OC'ing, you may want to just use the multi for your OC'ing for now and leave the voltage alone. And of course, you do all this at your own risk.
Always watch temps!
Note:
If you don't want to keep going back and forth in and out of BIOS, you can use AMD Overdrive to do the same thing while in Win. When you get a stable OC w/AOD, make those changes in BIOS so they are permanent.
http://www.techspot.com/downloads/4645-amd-overdrive.html