“I'm tired.”This is pretty straightforward. Whoever this is would like to go to sleep or take a serious power nap.
She shifted on the bed and could see her boyfriend's face transforming. Within the next five seconds the face she'd fallen in love with, the one that could still make her heart skip would morph into something unrecognizable. The contempt on that face always left greasy knots in her stomach. She sagged into her pillow. “I'm tired.”The context has changed the meaning of the dialogue. Yeah, she still might want to roll over and just sleep, but it's also to avoid what's going on. You can guess it's also about the state of her relationship with her boyfriend.
Good dialogue can stand on its own but great dialogue is about the context. So don't be afraid to use the context mercilessly.
“Hey.”The context is a greeting, but each one of these can tell you a lot about the character. It can tell you how they feel about the person they are talking to.
“What's up, sweet cheeks?”
“Oh, hi, ruin-er of all good moods.”
“Hey,” Tara said to her old friend.Also, just a big general tip:
“Hello,” Tara squeaked.
“What's up, sweet cheeks?” Tara bent down and placed kisses on her niece's full, round face.
Amir stepped into her office and all the air in her lungs whooshed out. She didn't care it was irrational for hating the way he made her feel a giggle away from embarrassing herself. She stood from her chair and smiled. “Oh, hi, ruin-er of all good moods.”
I really don't prescribe to the advice to write how people talk. It's problematic because:
People are incoherent when they talk. “Oh, um, er, you know the whachamacalit? You know what I'm saying.” (This is usually when you're talking to your friends and you know exactly what a whachamalit is.
Or, so verbose you can't parse the meaning.
Or, they are communicating some information, which is usually has some importance to the people who are talking to each other. But totally mundane to anyone else.
Dialogue is not talking. Dialogue is information you're imparting to a third party who isn't a part of the conversation.
So, make your dialogue interesting, entertaining, insightful and TRUE to your CHARACTER. And read it out loud for the rhythm, not to see if it sounds like “real people talking.”
“Got a sec?”
“Do you have a moment?”
“Dear sir, I need to impart some important information.”
Everyone would say the last is how no one in real life talks. Until you put that dialogue in the mouth of someone stuffy and who is probably someone's butler.
So...that's all I've got. Yes, a real post. But look out on Friday. There'll be promotion.