You could use a program like MSI After Burner, or EVGA Precision X.
I don't personally overclock anything, not even on my desktop rig. But I certainly wouldn't overclock a laptop, even if it is a 'gaming laptop'. Although the hardware is a lot more powerful than most run of the mill £250 laptops, the cooling simply can't match the performance of that of a desktop system, purely due to the form factor (which for the record is really fucking small.)
Also, I doubt you'd really notice all that much of a difference in performance. Because even if you did decide to OC, I would only push the clock up by a few megahertz, anything more than that and it will either crash the system, due to lack of power, or it will eventually over heat.
To go in to a little more depth, the coolers in performance laptops are rigorously tested to find the absolutely maximum temperature when the CPU & GPU are under 100% load. Whilst there's nothing to say that the cooler couldn't handle a little more heat, there's also nothing to say that it could, as the coolers are *only* tested to find their optimum temperatures whilst the chips are running at the their stock clocks. Hence why almost all manufactures warranty's don't support overclocking.
Hope this helped you out a little.