When you start up the computer there should be a prompt or something of the sort before you hear the POST beep for a normal start up. For me and my Asus motherboard, I have to hit delete to enter the BIOS set up. In the BIOS there should be options regarding voltages, frequencies, and others of the sort. It's in this menu where you should preform most of the customizing of clock speeds.
The one thing you want to do when overclocking to get the most out of your CPU is to get a higher FSB speed. A higher FSB speed means you keep a 1 to 1 ratio with your ram and your CPU. This ratio is quite important if you want to see any results. When Overclocking you want your RAM to increase in speed at the same time your CPU increases in speed. If you have your RAM faster than your CPU's FSB speed, then it defaults the point of a overclock as it creates a bottleneck. If your CPU is faster than your RAM then it is held back because of the RAM can't keep up with the CPU.
Now with your CPU from your sig, you want to have the highest FSB without giving up your CPU speed. (What model CPU is that?) So what you want is to raise the FSB and decrease the Mulitplier so your CPU is at the same speed.
For you, I would set it up to have a 3.2Ghz CPU speed. So, because an AMD platform's FSB is set to 200Mhz and useally has a multiple of 5(Equals the speed of the Hypertransport, confusing so wait for someone else so answer). So for you, set up the FSB to 210Mhz(take small steps) and the Multiplier to 15 so your CPU speed equals 3.15Ghz. Then if your stable, move up to 220Mhz FSB and a multiplier of 15(3.3Ghz) or 14.5(3.19Ghz) if you can set a half a multiplier(not sure, but I believe you can). Then if you can continue, Go to a 230Mhz FSB and a multiplier of 14 and you have a CPU speed of 3.22Ghz. Go as far as you can until you encounter instabilities or can't boot up. I personally don't like increasing voltages, but make sure you get the most out of that voltage change.
I have gotten my 5600+ to 3Ghz without a change in voltage by just changing my FSB. I don't have a unlocked multiplier (at least I don't think so) so I can't change my multiplier.
Happy Overclocking.