A couple of my favorite things while living in Paris:
- walking around just before dark
- learning/saying "Bonne Soirée"
Being quite honest, "bonne soirée" is just more fun to say... so when I started picking up on Parisians saying it when we parted ways, I instantly wanted to add it into my everyday usage. After giving it a shot and not getting the absurd "oh, silly American" looks, it was done! Fine - I did do my research on when/how it was appropriate. Doing that is often funny. Since these tutorials are typically written by natural French speakers, the tone is often "well, that's just when you say it - how do you not understand?" Basically you can use "bonne soirée" when you leave someone but the night is not completely finished - like "have a good evening." You can also say "bonsoir" in this situation and it is also correct. However, you cannot say "bonne soirée" when you first see someone in the evening - for that only "bonsoir" is used. Get all that?
THESE are the things they don't teach you in French class. We stopped at "bonjour" and "bonsoir" when there are so many other options & occasions where something else is more appropriate!