* "Hello, how are you doing?"
* "Hi, how are you getting on?"
* "Alright mate?" (this is a very informal way of saying hello, and is only really used among friends and family)
* "Good morning/afternoon/evening, how are you?"
* "How's it going?"
The response to any of these phrases is typically "I'm fine, thank you, and you?" or something similar. It is considered polite to ask after the other person's well-being when greeting them.