Embrace the culture
I cannot emphasize enough how important it is to learn a little about the place you are going before you go there! By no means do you have to be an expert however it does help to know a few of the basic cultural norms. From experience, not everything you hear about a country is true so start from a clean slate and be ready to learn a few things!
One of the requirements should be to know a few phrases in the local language. Hop on Duolingo and do two or three lessons, not just for France but for each new country you visit. "Bonjour", "Au Revoir", and "Parlez-vous anglais?" will help you a lot in Paris! I will personally tell you it's a custom to be polite in any country and if you are not curtious enough to say Bonjour before anything else, you will have trouble getting courtesy in return.
I also recommend seeing a play or movie while in Paris. There are so many fun options!
Learning basic French
Do you speak English?
Excuse me (getting server’s attention)
S’il vous plaît ...
Excuse me (like pardon me, apology)
How much does this cost please?
Combien s’il vous plaît?
I don’t understand
Je ne comprends pas/ je comprends pas
I would like…
The bill, please
L’addition, s’il vous plaît
Same word in french just Prounouced “wee-fee”
A table for two, please
Une table pour deux s'il vous plaît