If you're visiting Australia and are non-Australian but you do speak English, you should have no real problem understanding the local lingo. (We try to make sure we use only words that we think are common to your kind and our kind of English.)
Don't get into a blue. Know a bit of Strine and you'll be fine.
In a pub, you could get asked to shout. Don't holler your head off. You're just being reminded it's your turn to pay for the next round of drinks.
When There's Tucker and Grog
In a social setting, especially when there's tucker and grog, or just grog (or plonk), we do tend to slip into our dialect, which means: Hey, you're one of us, so none of this Queen's English bizo.
So whether it's this morning or this arvo, a few good words to know in the pub are middy and schooner, with a fair sprinkling of mate here and there. Don't be a mug or a lair, be fair and do your shout —reckon that's the go.
Listen to your mate's corker of a story, and don't go crook if you can't come up with your own ripper yarn. And don't tell the bloke to rack off, sport, or you could get into a barney and in all sorts of strife.
When You Need to Go to the Loo
If you need to go to the restroom, comfort room, or whatever else you call that room (because you're pissed, or simply pissed off), that place is the loo, or call it toilet. A dunny is a different thing altogether.
Whatever you talk about, don't act the wowser as everyone tends to be given a fair go, fair dinkum, mate. And don't go acting the yobbo either.
Also, it doesn't hurt to say ta or thanks for anything done for you; you'll hear a lot of taing around, thanks is so much a part of the Aussie language.
And So, Half Your Luck, Mate
Barney: Row, fight, argument.
Blue: row, fight.
Crook: Mad. Also sick.
Dunny: A more primitive type of toilet, usually located outdoors.
Fair dinkum: Genuine, real, really.
Fair go: Fair chance.
Grog: Beer, liquor.
Half your luck: Congratulations.
Lair: One of brash or vulgar behavior, usually flashily dressed as well.
Mate: Friend, pal, colleague.
Middy: Middle-sized glass. A middy usually contains 285ml (of beer).
Mug: Someone taken advantage of.
Pissed off: Angry, mad.
Plonk: Cheap liquor or wine.
Rack off: Scram, get lost.
Ripper: Great, something great.
Schooner: A larger glass for beer, larger than a middy.
Shout: pay for a round (of drinks).
Sport: Something like mate, but sometimes said with some belligerence.
Strine: Australian as she's spoke.
Wowser: Prude, puritan.
Yobbo: Someone a bit uncouth.