stuck,
if you need to do it, keep it vague.
“my sister got engaged recently” is much better than “yay, I’m going to Flatbush tonight for my sister’s vort”.
“Someone I know went to yeshiva xyz” is better than “my oldest brother went”.
With school, if you say that you’re nervous about midterms, no big deal – all schools have midterms. But if you say your school was just evacuated by the bomb squad, then you’ve just announced which school you go to – it will be in the news. This example actually happened here once a few years back. (I don’t remember if it was a bomb squad or whatever, but something about a school was in the news soon after someone posted that it just happened in their school. And yes, their identity was uncovered based on that together with other bits and pieces of personal info).
I’m not a posek but I would think that bending the truth a bit is ok, to throw someone off. If you don’t really have any aunts but talk about how much you enjoyed your aunt’s wedding, it could throw someone off you trail. Popa can probably give lessons on that. 🙂