Guys like this. EDIT: Actually, this picture just doesn't do justice - these guys wouldn't fit in with the hipster crowd in my area.
Typically:
Shabby haircut, if cut at all. Many seem to have erased the words "comb" or "brush" from their vocabularies. Alternatively, many have opted lately (it seems) for the 50's side part (think George McFly) or "duck tail" style. For women, the trend seems to be bobs or shaved sides, especially if it can be made to look like someone hacked at it with a dull steak knife.
Facial hair: Not to bag on all facial hair, but growing it out without trimming, washing, or any other sort of grooming. Alternatively, there is a subset within the subset of over-manicured beards/mustaches hearkening back to the "lumberjack" era.
"Skinny jeans" which means pants legs that most probably can barely fit an ARM into, yet somehow they pour themselves into these jeans, which are also frequently "bagged" at the waist. You will see them sometimes holding the waistband up even though there is little threat of them actually falling below the hips. Also identifiable via brightly-colored metal stud belts, also frequently sporting chains.
Flannel or polyester shirts, typically button down or polo, typically dirty or otherwise "relic'd" and with the sleeves either rolled all the way down (but unbuttoned cuffs) or tight-rolled, if the sleeves haven't been cut off altogether.
Thermal long-sleeves regardless of weather conditions are a staple, as are vests and/or twill/tweed sport jackets. Also, ironic t-shirts from the 80's are highly looked upon, although the more "mainstream" cartoons and shows are less acceptable than the short-run, low-budget stuff.
Scarves are a must-have, the more garish the better, to a point. Plaid is the working word here.
Square-framed glasses, sometimes taped or glued (regardless of whether that is necessary to hold them together).
Beat up shoes, often with the long, pointy square toes or very beat up New Balance/otherwise not-popular and cheap tennis shoes. Bonus points for Velcro straps. Alternatively, "combat" boots with jeans tucked in sloppily, untied.
Ironic headgear - beanies with fuzzy things at the top, hats (not trucker hats) that express some childish or out-of-date sentiment. Fedoras and bowlers must be odd material and cannot match anything else you're wearing.
ANY cast-off Army surplus stuff, as long as it looks well-used, in many cases pipes or clove cigarettes, and political pins/safety pins holding stuff together. Duct tape also scores big bonus points. Anything checkered or otherwise gaudy patterns are a plus, as is wearing grandma's shawls or couch doilies. ANY "gauged" or oversized piercings, and tattoos on the neck/hands are extra special bonus points when combined with any of the above.
That's the fashion around here for the hipster crowd.
The mental attitude is one of complete apathy, anti-coolness. If you think something is cool, the hipster mentality is to either deride it
and/or claim to have liked it/done it BEFORE it was cool. Music with any sort of production value (aside from being poorly recorded on a one-track in a bathroom/garage/garbage can) counts as "mainstream" and unworthy of attention. Books that aren't classics, philosophical (only if it's anarchistic/atheist/amoral) reading, and "underground" media is all that hasn't been "tainted by corporate America" and the only good movies are the ones you have to read or that don't have a real plot.
Anything commercial is bad, and making ANY sort of profit is evil. If they work (and many do, to be fair) it's typically in a tech job or low-paying entry-level job, or jobs that are typically understood to be held by the other gender - i.e. man working as hairdresser (not barber, and there is a difference) or woman working construction labor.
Did I miss anything?
EDIT 2: Oh, I forgot. By and large,
in my experience, REAL hipsters believe Ron Paul will save the nation, if they can muster up enough energy to care about politics - which, surprisingly, they tend to take pretty seriously.