The film on the outside of the glossy screen is PLASTIC, folks. It's SOFT.
Do not use dry paper towels. Paper towels are not always very soft. It only takes one piece of grit that's harder than the plastic film.
Do not use canned air. Compressed gas is very cold upon exit from the can. I'll just leave it to your imaginations what a burst of sub-zero Celsius in a tiny concentrated spot might be able to do to your LCD. Plus the chemical- WTF is that?
If you ever sneezed or coughed on your screen while you were working, and residue dried there in tiny speckles, you know that no canned air is getting it off. Canned air isn't going to remove a finger print, either.
Alcohol? Apparently, it doesn't seem to harm the plastic coating, according to the fact that nobody's has come forward with such a report. But for finger oil, alcohol will just cut the oil, allow it to be smeared around, and then evaporate, still leaving a film of oil.
I use a microfiber cloth, moistened, with a tiny drop of Dawn dish detergent worked into it. It cuts finger oil, removes the dust, and leaves no streaking. The trick is not to use too much detergent.
-But rubbing on your screen with a dry paper towel is foolish.