Formal:
* Aloha kakahiaka: Good morning, welcome.
* Aloha awakea: Good afternoon, welcome.
* Aloha ahiahi: Good evening, welcome.
Informal:
* Aloha: This is the most common and versatile greeting, meaning "hello" and "goodbye" as well as "welcome."
* E komo mai: Come in, welcome.
* E komo mai i ka hale: Come into the house, welcome.
The best way to say "welcome" in Hawaiian will depend on the situation and the people you're speaking to.