Whether you’re listening or reading, thick dialects can be hard to understand – partly because it takes experience with a specific dialect to understand it easily. It’s kind of like reading messy handwriting. Once you’ve experienced it enough, you can read it, but for a first-time exposure, it’s pretty impossible. That’s why a lot of the accents you’re exposed to in real life are thicker than you’ll want to use in a book (unless, of course, the character is supposed to be unintelligible). That’s also why when you’re writing dialogue, relying too much on the way you’ve heard people talk can be detrimental (because real people don’t talk the way they do in books).
That’s when acting methods for dialect can help.
When stage actors learn to speak in a dialect, the main goal isn’t to speak exactly like people from a specific country or region. Instead, they focus on a few specific vowel and consonant changes that are commonly associated with that dialect. Those changes along with the placement focus are all that’s needed because the goal is not to duplicate the dialect exactly – you only need to suggest it enough that others can recognize it.
Changing only the sounds that epitomize that dialect accomplishes that goal without losing clarity. That’s why they’re called stage dialects, not just dialects. This method can be useful for your writing, too. Try to think of the minimum changes you can make to the spelling to suggest the dialect you want. The fewer changes you make, the more intelligible it will be.
Of course, figuring out those changes for yourself can be hard. If you live near a college or university with a good theatre program, you can always talk to the dialects teacher and get some tips. But what if you don’t?
Well, there are other ways. There are plenty of people who make a living out of dialect coaching and/or who sell products designed to teach you what changes to make for a specific dialect. The UCLA Library has a site that specifically lists dialect resources. The dialect instruction books and cds by David Alan Stern or by Paul Meier can be found on Amazon and can generally be bought by separate dialects or in sets grouped by area.
There are also free dialect and accent archives that you can listen to (they’re listed on the site); however, those won’t tell you what specific vowel and consonant changes to focus on. If you feel confident about your ability to break down the dialect into the sounds that are most recognizable, then, these could be a cheap tool, but I can tell you from experience that some people learn best when they have the paper explanation to guide them, as well. It all depends on how you learn.
If you’ve never studied dialects, I’d recommend starting with the cd and book for a dialect you want to work on. Following their instructions will give you a feeling for analyzing and breaking a dialect down into parts. After some practice with that, you may feel ready to break out on your own and do your own analysis. Or you might like the cd and book so much that you consider it a sound investment, especially if you like using a variety of dialects in your writing.
However you want to learn it, having a strategy for suggesting dialects can help your writing. Wouldn’t want to confuse people, now, would we?