I use: 1 part of whatever cleaning solution you want, be it alcohol, windex, whatevs, I use windex, and 5 or 6 parts distilled water, NOT tap water (prevents smearing/streaking).
I think the most important part of cleaning an LCD screen is NOT using paper towels or rough rags, which scratch up the screen. Don't use tissue paper, I think that stuff has lotion type stuff that smears up the screen.
Use that soft blue microfiber stuff or those camera lens cleaners or a really soft piece of cotton. Don't spray the cleaner directly on the screen either or you could get liquid where you don't want it. Spray it on the cloth.
I think the most ridiculous thing I have ever seen one of my friends do was use toothpaste to clean their screen. Needless to say, he was unsuccessful.
There! A nice lengthy post on screen cleaning. May it never be forgotten.
