Well, first you need to figure out whether or not your motherboard will even support overclocking.
Then, if it does and you're truly interested, learn a thing or two about what overclocking actually is, what exactly is happening and how it effects the components and buses in your system. There are tutorials all over the place that cover the essentials, I know AnandTech had a good article on it. I'm sure if you search these forums you'll find something as well as I've seen (and answered) comparable questions on multiple occasions.