If you are a graduate research student, particularly if you have elected a field in humanities, the other human beings (including your undergraduate students if you’re tutoring) will only know one thing about you for sure; you’re supposed to be writing a thesis.
This is quite dangerous, because they’ll then ask what your thesis is about. As anyone who is a research student not in the final ten minutes of their candidature knows, this is a touchy, raw topic of discussion. People who are not research students tend to think they are being kind, and taking an interest by asking you about your thesis. There are two ways to deal with this sort of interrogation. The first (and infinitely more sensible way) is to have a prepared answer, I like to think of it as the thesis-pitch. This also does well when your undergraduates ask. The problem with the thesis-pitch method comes with further questioning. Either you can’t answer your interrogator without outlining a brief history of contemporary cultural theory so you can show them where your idea fits in, or (much more likely) you don’t actually know the answer to their question. Both scenarios end with you looking like a dickhead.
The alternative method of engaging in thesis-related discussion involves reeling off the names of a few theorists and cultural artefacts (or whatever you’re writing about) that are so obscure as to put anyone off further questioning. There are two consequences of this technique; the first is that most people will inevitably think you are both a dullard, and a wanker. The second, is that very occasionally, someone will be around who actually does know what you’re talking about who will continue their investigation. You then find yourself being forced to defend an argument you barely understand and only just came up with the other day when pushed by your exacerbated supervisor. See above, re: dickhead.
There is, of course, the possibility that you have done enough work that you do know what your thesis is about, and if that is the case, I don’t see why you’re reading my advice in the first instance. Go and be a famous theorist instead, why don’t you?