Formal:
* J'espère que tout se passera bien. (I hope everything goes well.)
* Je vous souhaite bonne chance. (I wish you good luck.)
Informal:
* J'espère que ça va bien se passer. (I hope it goes well.)
* Bonne chance ! (Good luck!)
* Tout va bien se passer ! (Everything will go well!)
Specific situations:
* Bon courage ! (Good luck! - This is often used when someone is facing a challenge.)
* Je te souhaite une bonne soirée. (I wish you a good evening.) - For a social event.
* Bon voyage ! (Have a good trip!) - For someone traveling.
Choosing the best translation depends on the situation and your relationship with the person you are talking to.