You will not be able to do it the 'real' way (ie with calibration equipment and using your TVs service menu) without training and expensive equipment, plus without experience you'd run a great risk of ******* up your TV. Probably the best thing to do is buy a calibration DVD and walk through that, it'll go through several steps that help you optimize all of the 'normal' settings on your TV for your room's light, acoustics, etc (it'll also help with audio). The one I've used was the consensus recommendation on AVSForum.com, and is called 'Joe Kane's Video Essentials'. You can get it on Amazon for under $20, and if you've got a Blu-Ray player they've got a new BR version as well...
Go to AVS forum and search for your set and someone(or multiple someones) will have posted the calibration settings they got for it and how to access the service menu to make the changes. It won't be an ISF calibration but it will be much better than what you have out of the box. The Link
As the above poster suggested, go to AVS and look for your TV. I did it for my TV and it looks awesome; however, it took some getting used to because the "ideal" calibrated picture is much more warm (red-whites) and smooth than you are probably used to. If your TV has a movie mode, it willl be much closer to that than the normal or optimal modes. Those are much brighter (blue-whites) and crisper.
