The workhorse of conveying tone and delivery within dialog is punctuation. Dialog certainly can follow the standard English rules for punctuation, but often it doesn’t. The differences are as much about leaving out “required” punctuation as they are about adding more or less of it than the usual rules would require…which is a major reason why knowing the actual rules of punctuation is vitally important for professional fiction writers.
If you don’t know where the comma is supposed to go, or whether you’re supposed to have a semi-colon, a comma, or a dash in a particular spot, you are unlikely to be able to alter your punctuation effectively. In the worst case, a writer can end up punctuating a line of dialog with the intention of emphasizing one particular emotion, but end up actually using standard punctuation that reads neutrally for most people (i.e., not emphasizing anything).
Except for stammering and/or dropping letters (“He’s goin’ to the store. I ‘eard ‘im say so.”), punctuation doesn’t work like word choice – that is, one doesn’t come up with an artificial rule and assign it to a particular character’s dialog. This is because punctuation reflects delivery, tone, and cadence, and almost everybody delivers different lines of dialog differently at different times. People don’t ask questions in the same tone that they use to make demands, give orders, or deliver a thoughtful opinion. They don’t deliver commands the same way they whisper sweet nothings in their fiance’s ear.
Punctuating the same words in different ways can completely change the meaning of a line. The classic example is “woman without her man is nothing,” which can be either “Woman, without her man, is nothing.” Or “Woman! Without her, man is nothing.”
Punctuation can be used to indicate that someone is speaking rapidly or in a kind of breathless hurry. It’s commonly used to indicate stammering, longer pauses, and words or sentences trailing off. Consider the difference between “Oh.” and “Oh!” and “Oh…” The first is neutral. It has some room for a reader to choose tone, but I’d never read it as excited or surprised. Similarly, the second, with the exclamation point, has more emotion and tone; it reads easily as excited or surprised or frightened, but not as, for instance, the flat tone in which a teenager might respond to “You have detention.” And the last one indicates trailing off – possibly thoughtfully, possibly because the character is ashamed or humiliated not to have thought of something that’s just been explained, possibly just because they’re not paying attention or are distracted.
What this means is that the author can use punctuation to indicate (to some extent) the way a line is delivered. Dashes and ellipses are particularly useful for this. For example:
“I’d like to have tea with my friend.”
“I’d…like…to have tea with my friend.”
“I’d like to…have tea with my friend.”
“I’d like to have tea—with my friend.”
“I’d like to have tea with my…friend.”
“I’d like to have tea. With. My. Friend.”
The first version is a plain straightforward statement. In the second, the speaker hesitates (indicated by the elipses) both before and after “like,” which implies that he/she was considering some other word (or possibly that they’re surprised to realize that they would actually like doing this).
In version three, the hesitation comes after “to,” indicating that the speaker wasn’t quite sure what they’d like to do, and had to take a minute to come up with it. I’d use this when the speaker isn’t used to having his/her likes considered, or when the thing they’d like to do is unexpected (as it would be if the preceding line was “Sir, what would you like to do with this traitor?”).
Version four is the only place I used the dash. Like ellipses, it indicates a pause, but ellipses tend to feel more uncertain and/or hesitant, like the voice trailing off at the end of the sentence, or someone pausing to think before deciding what comes next. A dash is more of a deliberate pause for emphasis, making a point of the fact that the speaker considers that person “my friend,” and/or doesn’t want to have tea alone. Quite possibly the speaker is contradicting something the previous speaker said. If I’d wanted the declaration to seem more tentative, I’d have used ellipses instead of a dash; if I’d wanted it to be more emphatic and/or a bit annoyed, I’d use a period and then capitalize “With my friend” as a sentence fragment.
Version five, like version two, uses the ellipses to indicate that the word choice was in doubt. Maybe the “friend” is someone who was an enemy two chapters back, or a former or prospective lover; that part, the reader has to infer from context. All the punctuation can do is imply that the speaker wasn’t sure what to call the person.
The last version is an extension of version four. By punctuating “With. My. Friend.” as three one-word sentence fragments, I’m indicating that the speaker is emphasizing each individual word very specifically, biting them off because he/she is somewhere between seriously annoyed and really angry. “With! My! Friend!” would, I think, be over the top in the majority of cases, though I might use it if the speaker were shouting.
One can also use a lack of spaces or hyphenation to indicate that the speaker is talking very fast; “Iwouldliketohavetea” and “I-would-like-to-have-tea” differ mainly in their readability. This is useful when the dialog in question is short and uncomplicated; longer, more complex sentences usually get a hurried feel from leaving out the commas and/or semicolons.
Different writers (and readers) have different tolerances for the degree to which they use punctuation changes to indicate dialog tone and cadence. Don’t feel obliged if you hate the technique. Also, like most things in writing, nonstandard punctuation works best if one doesn’t do it too often. There was a Romance writer some years back who was notorious for writing heroines who could not get through a single line of dialog without it being interrupted by at least three sets of ellipses (sometimes as many as six in one line).
Does the narrator’s voice count as “dialog” for applying these techniques? Especially if it’s a work in first-person?
Also, character thoughts not spoken aloud. Characters would mostly think the way they talk, except maybe for mispronunciations, accents, and verbal tics. Wouldn’t they?
I’ve used these techniques in narration, writing close-ish third person. Especially ellipses: But first, she’d have tea with her…friend., if there’s real doubt at this point whether the person is actually a friend, for example.
I don’t recall anybody objecting to it.
I would definitely think that thoughts follow dialog “rules”. Doubly so if you’re setting them apart with italics or some such.