Overclocking a graphics card?

I have a graphic card and thinking to overclock it, so i can get more improvement in graphics
What is the procedure for overclocking a graphics card?

Overclocking your video card resembles overclocking your CPU, albeit a bit more simple: you’ll gradually bump up your graphics card’s core frequency, evaluating it for stability with a benchmarking tool each time you press it a little further.

steps that you have to follow

Benchmark your stock settings
Increase Your Core Clock and Re-Benchmark
Increase Your Voltage and Memory Clock (Optional)
Run a Final Stress Test and Play Some Games

Time is cruel to your hardware, especially expensive graphics cards. All glory is fleeting: after a while, even mighty leaders like Nvidia’s once unstoppable GTX Titan move from first place to shabby and outdated, making way for the best graphic card of the next generation. The upgrade cycle is relentless, but there are alternatives to busting your budget on a new GPU every single generation. You can make your current graphics card faster, and potentially get dramatically better performance out of it, by over clocking.

Thanks for your reply, does it effect on my gaming performance ?.

It will increase performance, unless you’re thermally limited in which case it will start downclocking itself for safety.

If you live in a hot area and overclocking simply makes the card too hot, you could consider an undervolt. You remove unnecessary voltage and it allows the GPU to sustain boosts a bit longer because it’s not thermally/voltage limited.