if I just want to overclock....

You would have to Root it, install a Custom Recovery, and then install an Over Clocking kernel

 

check out Overclocking link in my sig to find out more

 

Only the root part is correct

Froyo FRG22D with the stock kernel allows for overclocking to 800mhz.

If you want to overclock beyond 800mhz you would need a custom kernel.

 

Just like everyone else said you would have to root your phone first. If interested in rooting you can click the link in my signature to follow a step by step guide on how to root (Thanks to the genius Motocache1). Also most of the custom roms already overclock your cpu by default. But also like everyone else stated you can install a kernel if you are looking for more speed. You should def check out the custom roms though with the themes. Every since I installed a custom rom and theme it has made me love my phone even more hahahhaha. If you were looking for a good rom to start out with I would say swing on over to the Liquid rom section. Im currently running the new Liquid rom v1.6 with the watermarkd theme and its great. Plus the default kernel has your cpu running at default 1000mhz. Its super fast and smooth. But everybody has there owns preferences. But you can check out the list of roms or liquids below.

Custom Roms Link

Liquid Roms