The unwary aspirant of graduate studies enters a pitfall of semiotics that is hard to navigate. After all, academic life presents a facade of breeziness and nonconformity; but this covers like a doily the careerist conformity that is there like a bad cold or pizza boxes on the floor of a guy's apartment! The Sheep (the Academic Elect) and the Goats (not our type) differentiate themselves in varying ways.
The way that most outsiders is familiar with is politics. Be impeccably liberal in your overt stance: wear your affiliation on your sleeve, or at least on your auto bumper. Remember: MSNBC, not FOX News. Read the NY Times on weekends, not the Tennesseean. Vote in nonconforming ways secretly; if you must, be a closet Liberterian or Green Party member!
And speaking of autos, never, never drive a SUV or a Ford or Chevy. A Mini Cooper gets maximum points; but a Volvo or an Acura is okay if one can't avoid one's social background. Accords are too bourgeois, though Japanese. Guys owning a Corvette should expect comments about this being in response to certain, ah, anatomical inadequacies. Other grad students can be bitchy.
Get an accent. Something like received English or Bostonian, or middle European. Use tortured syntax like you were educated in Heidleberg. No drawls, twangs, and nothing that sounds like Sarah Palin or Jeff Foxworthy.
Furniture and decor: homemade bookcases, using boards and bricks, cast-off furniture. Nothing from Pottery Barn, except for in that room in which no one, even your closest friend, ventures. After all, loose tongues sink academic careers. Classical art deco posters: yes; Brad Pitt or Heath Ledger posters: no. Chuck Norris posters are triple no-no-nos!
Dress is a matter of importance: strive for functionality by wearing jeans and tops that are in natural colors. Watch Legally Blonde, and don't go there when it comes to fashion. Beware of t-shirts bearing ironic messages; they might be misconstrued as an expression of a non-academic disposition.
Footwear is especially important: sensible shoes should reign. No heels, please. And no bitch shoes! Keep thy bitchiness to your discourse.
Even lingerie is a criterion. Nothing colored, except maybe black. Think grannies, not bikinis or thongs. Reject sexy in favor of functional. Even though no one will see it, in your heart you know what you're wearing and it's not for you if you want to seem erudite.
Choose your music with care: Mozart is top of the line, but romantics such as Beethoven will also do, if not played too often. Progressive or retro jazz is in good taste. Blues is okay. Country music is OUT! Let not a Britney Spears CD be seen in your area.
The literature you won't ever get to read should be impressive: the kind that you would not mind people seeing that you were reading should you die when the book is only half-finished. Obviously, keep your bodice-rippers or fan mags under wraps. You want to seem literate. A book in an esoteric language would do it.
Religion: Presbyterianism or Episcopalianism or Unitariansim are all held in highest regard within academe. Or belong to to some fairly liberal Catholic or Methodist church. Attend irregularly. That's the key.
Then there's the matter of one's significant other. Generally, a live fiancee, boy friend, or lover is too high maintenance and requires too much time. It's better to have an absentee one. Someone at a med school or law school elsewhere, preferably a first-rung institution, like Harvard or Princeton. You don't get many points if he's at Alaska Polytechnic and Beauty School. If an absentee one is unavailable, then acquire a virtual one over the internet, being mindful never to meet said person.
Obviously, having an absentee Mr. Darcy or Indiana Jones would trump even those.
I hope this gives you some general notions as to fitting in academe. Remember: you van't ever be too pretentious!