Heshy Fried gives this guide to sounding more religious, more Orthodox, than you really are:
Funeral: Say Levaya instead
Death, died or passed away: Nifter is the supreme substitute, if you want to be a bit more moderishe, but not really too unfrum you should use passed away – but always follow it up with zecher tzadik lebracha, ava-shalom or of blessed memory if you want to sound conservative.
How are you doing: The correct response is always to insert Baruch Hashem before whatever you want to say – so if your dog (obviously a BT because frummies are afraid of dogs because it’s a mesorah from the shtetl that the goyim had dogs during the progroms) died and someone says “nu, shmuely, vus mach-du” the correct response would be, “Baruch Hashem my dog was just nifter” and so on.
Friends: Your friends are no longer your friends, homeboys or crew – they are now called your chevra.
Israel: Always called eretz yisroel.
Kiddush Cup: Call it a becher from now on.
Gays: Of you ever talk about the gays at all, you have to throw in words like “toevah” and be sure to spit when you say it.
Meal: No longer is any meal just a meal, now you should call it seuda. Shabbos Meal becomes shabbos seuda.