Help Overclocking my AMD 1.2 CPU and IWILL Ka266MB

[Jetstreamp]

I am new to overclocking and I have an AMD 1.2 T Bird CPU and an IWill Ka266 Motherboard with 256MB Crucial pc2100 DDR Ram. When I go into the bios I see where you can set the Mhz up to I think 148 and when I do that My cpu runs at 1314. How is everyone getting so much more out of there cpus? Please let me know with detailed instructions on how and what to do. I see where you can change the cpu Core volts But I have not touched that.