Dialogue is the representation – as opposed to replication – of realistic conversation.
By this, I mean that it should sound like real life conversation, to a point – but not entirely.
It would be better to consider character dialogue in terms of edited highlights.
In reality, people ramble, go off at tangents, and frequently use phrases such as “um” and “er”. This is boring to read through, so keep it concise and readable.
As with all aspects of telling a great story, conflict is necessary.
Pleasant conversations, where all is happiness and light, and there is no disagreement or problem between your characters, are pointless.
Cut to the drama, wherever possible. Remember that dialogue is a tool, and should be used to move the story forward.
Use dialogue to develop your characters.
Differentiate the dialogue of various characters, in as many ways as you can. Consider the range of vocabulary that each would use – individual word choices.
When you actually reach the point of being able to “hear” the characters talking, in your own mind, you will know that you have created real people.
Then, you will know instinctively, if a line of dialogue doesn’t fit – because it will not be something which this person would actually say, in the particular context.
A major role of dialogue is, as I mentioned, to move the story forward.
As such, dialogue is often the perfect place to convey necessary information. However, be careful not to “info dump”. Dialogue must sound natural.
And, on the subject of natural sounding dialogue – please take care not to overuse character names.
“Hello, Mary. How are you today, Mary?”
“Hello, Tom. I’m fine, thank you, Tom. How are you, Tom?”
Okay, so it’s not normally this bad – but, at times, can come close.
Pay attention to real conversations, and you’ll realise that we don’t generally use each other’s names that often: mainly at the start of our interactions, or when trying to emphasize a specific point.
Said is not dead.
It’s generally much better than “exclaimed” and the like, which draw attention to themselves, and are principally used for the sake of it, in a misguided effort to keep dialogue “interesting”.
Some variations, such as “asked” and “yelled”, have their place, but “said” is an “invisible” word, and should be your default option.
Mix it up with action tags, and instances where no tag is used at all. The latter is more difficult when three or more characters are present, but can be used effectively in dialogue between two characters.
Make use of subtext in your dialogue.
It’s unrealistic, as well as tedious, for characters to say exactly what they mean, at all times.
Multiple layers of meaning add that subtle touch, that will make readers believe in your fictional people and situations.
Hopefully, these tips will help you to write believable dialogue – an essential aspect of creating strong, and highly relatable, characters.
My posts on character development and describing locations in realistic fiction, may be of interest. Also, some additional thoughts on writing convincing dialogue.
I would also recommend a post from Standout Books, for another perspective on the subject of writing awesome dialogue.