This is an incredibly musical dialect. It has both a strong lilt and a fair amount of breathiness to it. Imagine a young lass dancing on her way home from school, knowing that there's a market fair that weekend. The sound is generated higher up in the mouth than Standard American. The lilt is created by having the vowels end at a lower pitch than they begin (see the suond changes, below).
As a side note, in reality there are almost as many variations in irish dialects as in English. Ulstermen speak very differently from Dubliners, for example. The dialect presented here is a sort of Generic Stage Irish, and should not be taken as representative of the speech of all Irish-speakers.
Irish Syntax
The Irish have but little sense of hierarchy, unlike their English neighbors. They are also a very friendly, open people. Therfore, the irish call everyone except the monarch "thou."
Everything is a story to the Irish. Flavor your speech with lots of "Well thens" and "nows," as in "Well then, I was walking along," or "Now, I was aboard ship, when..."
You can insert the word "after" between any passive verb and the gerund which follows. Oh, dear, that's a bit technical, isn't it? Here's a couple of examples:
I'm going to the privy.
becomes
I'm after going to the privy.
He was drinking.
becomes
He was after drinking.
The Irish use "lad" and "lass" more often than the Scottish "laddie" or "lassie." Like the Sctos, however, the Irish will use these terms regardless of age.
Sound Changes
Each of the links below is an ".mp3" file demonstrating a sound change. Listen to the example as many times as you need to, repeating it on your own afterwards. Take as much time as you need to with each sound. If you take the examples in order, you will sometimes run into sounds you haven't gotten to yet. Don't worry about it, just do the best you can until you've gone through all the sounds. Then go back and listen to the examples again, and make whatever corrections you need to.
Notice that this last change is carried quite far, almost to a long 'a.' The only thing to beware of here, is that you must not change to meaning of the word.
Finally, here's a spoken version of the chorus from Red Is the Rose to practice with. I recommend using this verse to get into dialect before rehearsal or performance.