In the past I have discussed the importance of finding a compelling time and place to give your story an interesting layer.
But don’t forget about language.
I just finished this article about Mad Men. It’s an interesting look at the language spoken by the characters on the show. Yes, they are living in American but the expressions they use are definitely of their time and place.
As an exercise:
Where and when does your story take place? What language do your characters speak? Is it considered an upper or lower class dialect? Which expressions are common to their time?