Formal:
* "Adiós." This is the most common and formal way to say goodbye.
* "Hasta luego." This means "see you later" and is a slightly less formal way to say goodbye.
* "Que tenga un buen día." This means "have a good day" and is a polite way to say goodbye.
* "Que le vaya bien." This means "have a good one" and is a more casual way to say goodbye.
Informal:
* "Chao." This is a very informal and common way to say goodbye, especially among friends.
* "Nos vemos." This means "see you" and is a common way to say goodbye.
* "Hasta pronto." This means "see you soon" and is a less formal way to say goodbye.
* "Que te vaya bien." This means "have a good one" and is a common way to say goodbye among friends.
Regional:
* "Güey." This is a very informal way to say goodbye in Mexico City.
* "Ándale." This means "go ahead" and is a common way to say goodbye in some regions of Mexico.
Other:
* "Cuídate." This means "take care" and is a common way to say goodbye, especially to someone you care about.
* "Te quiero." This means "I love you" and is a common way to say goodbye to a close friend or family member.
It's also common to use gestures when saying goodbye, such as waving, giving a hug, or kissing on the cheek. The best way to know how to say goodbye in any given situation is to observe how others are doing it.