Like most things in life, no pain, no gain.
Although most motherboard manufacturers will include software that allows slight overclocks from within the OS, the best results come from tweaking at the BIOS level.
Just read on the subject, ask questions on forums and study your motherboard manual (which can be downloaded as .PDF before you purchase your motherboard), overclocking does'nt require a PhD in quantum physics.
By the way, you can't really screw up (unless you physically damage a component due to gross negligence like running your CPU without an heatsink or shoving 4.5V through your RAM), if your system refuse to boot after you changed a BIOS setting, just turn off the PSU, remove the CMOS battery and clear the CMOS with the appropriate jumper.