Originally Posted by rip
If one wants to witness first-hand a microcosm of the decay and coarsening of the culture, one needs only to look at the clothing worn by most air travelers. One needs only to dress like a jackass to be treated like an animal.
If one wishes to appear increasingly out of touch with the culture at large, hopelessly mired in narcissistic nostalgia for a time that never actually existed, one needs only to begin claiming that the sartorial habits of air travelers, in some mysterious manner, signify growing cultural decadence. One might also write entirely in the third person, thereby increasing the reader's sense that the author simply does not understand how to scale the formality of a behavior, be it dressing or writing, in a way that is commensurate with the seriousness and formality of the situation itself.
I wear jeans, zip-up boots (easier to take them off at the metal detectors), and either a collared long-sleeve shirt with a jacket or, for thoroughly casual flights, a t-shirt and a hoodie. If I think I'm going to sleep on the flight, I'll pack a hoodie regardless, for the reason globetrotter mentioned.
I've thought about flasking before, but I always assumed they would be forbidden and that I'd get my flask confiscated at the security check. I'm not sure why, except that I assumed that the airlines would have regulations against it in order to force you to buy alcohol.
I have at least a liter of water with me on all flights as well.