Formal:
* "A bonu viaggiu!" (ah bo-noo vya-jee-oo) - This is a literal translation of "Have a good trip!" and is appropriate for wishing someone well on a journey or a new endeavor.
* "A Dio!" (ah dee-oh) - This is a more general phrase that can be used for "God bless you" or "Good luck," and is suitable for a variety of situations.
* "Tuttu a bonu!" (toot-too ah bo-noo) - This means "All good!" and is a slightly more informal way of saying "all the best."
Informal:
* "Bonu!" (bo-noo) - This is simply "Good!" and can be used as a quick way to wish someone well.
* "A tutti!" (ah toot-tee) - This means "To all!" and is a more playful way of saying "all the best."
* "In bocca al lupo!" (een bo-cca al loo-po) - This is an Italian phrase that literally means "In the mouth of the wolf!" and is used to wish someone good luck. It's a common phrase in Sicilian culture.
You can choose the most appropriate phrase depending on the situation and your relationship with the person you are talking to.