You may have the luck of the Irish, but you'd better work on getting the sound.
Step 1: Watch and learn Listen and learn. The best way to learn any accent is to observe and imitate it. Find speakers with the accent, or look for authentic examples of it in movies or audio recordings.
Step 2: Match inflection Match the famous lilt, or pitch pattern of an Irish accent. Practice by starting a sentence speaking a little higher than your natural speaking voice, lower the pitch in the middle of the sentence, then raise it slightly at the end.
Step 3: Change the vowels Change the vowels. Elongate the "aw" sound in words like "father" and "ball," and the "ow" sound in words like "town."
TIP: "Been" is "bean" in an Irish accent.
Step 4: Learn consonants Learn the consonants. Elongate "r" sounds and pronounce them harder. Pronounce "l" sounds harder and drop the "g" from "i-n-g" endings.
Step 5: Use colloquialisms Use colloquialisms. "Ossified," "fluthered," and "in the horrors" are synonymous with drunk. If something is good, it's "deadly." If you've ruined something, you've made a "right bags" of it, and the expression "What are you like?" means "I can't believe you're so dumb." Most British colloquialisms are also acceptable.
TIP: Avoid using cliches like "top o' the morning to you" and "blarney" – unless you're in a leprechaun costume.
Step 6: Use it Take your accent for a test-drive. Just make sure you go where it'll be appreciated, not someplace where it'll seem annoying or like you're making fun. Cheers!
FACT: According to a survey in the UK, the sexiest accent is Northern Irish.