There's a great Seinfeld episode in which George, in order to not be such a repugnant human being, decides to do everything opposite of what he'd instinctively do. The result is that he gets the job of his dreams and starts dating women way out of his league.
The entire series of Girls could be approached in a similar way. While I enjoy its bleak and cringe-inducing criticism of self-absorbed Brooklyn hipster culture (as well its female-centric focus, which the media needs more of), the show is also quite useful in dishing out life lessons as a guide on how NOT to live. If you want to be perceived as a compassionate and mature human being, you would do well to carefully take note on how the characters on the show (to be honest, mainly Hannah and Marnie) behave and do exactly the opposite.
And if you find that your behavior parallels theirs too much, you should probably take a moment to ponder a serious turn in the arc of your life.
So here are some anti-etiquette lessons from Girls:
1) When friends talk about their problem, actually listen and get them to open up more if they want to; absolutely DO NOT pivot to talk about your own issues or experiences
2) Don't tell rape jokes at job interviews
3) Don't use funerals as professional networking events (or at least be very tactful about it)
4) Don't only call your parents when you need something
5) Don't live through life's moments as chapters to be written in your grand memoir about your great self that's lived all of 25 years
6) Don't use other people's celebrations as opportunities to promote yourself
7) What's good news for you may not always be good news for others; and if there's any doubt, DO NOT drop this news on them before their Big Moment (like a Broadway premiere)
8) Don't say aloud about how you wished you spent a semester abroad in Africa and saving the continent if you want to sound intelligent
9) Don't assume that you know better when people tell you that their family members are fucked up; they've only known them for, you know, their whole life, while you're clueless
10) Don't steal, especially from people less well-off than you
11) Don't ask for feedback on a piece of writing from the person who's the object of ridicule in said piece of writing
12) Don't let others treat you badly just because you think having a sad backstory makes you a more interesting person
13) Don't resort to the "Your dad is gay" insult if you want to seem non-childish
14) Don't remain best friends with people you hate