We've all had friends quoting characters from their favorite television shows and movies. Some lines are almost as legendary as the programs themselves, and yet, some people aren't aware of what's involved in writing great dialogue. There are a few things to be considered.
1. Keep it fresh. We don't need to hear the same lines already overused in television, books, and movies. The only exception is when it's being used on purpose to be ironic. For example, in The Devil May Lie, there's a point when Jorge Hernandez, a bloodthirsty criminal, quotes a line from I Love Lucy that greatly contradicts the lighthearted comedy from the '50s. I think he might even have a gun to someone's head when he uses the line, "Lucy, you got some splainin' to do."
2. Keep it interesting. Let's bypass the same boring conversations you'd have with your great aunt at a wedding. Avoid talking about the weather (unless it's relevant) and the "hi, how are you?" dialogue, if at all possible. I only use something like this if purposely trying to show awkwardness in a conversation. People are bored enough in real-life conversations, so keep your character's dialogue engaging.
3. Don't ramble. I'm the queen on rambling (which you'll know if you ever watched my YouTube channel π) but when it comes to characters, make them get right to the point. Don't beat around the bush. Storylines are limited to a certain amount of many pages. Your job is to get everything packed in tight like a suitcase about to be weighed at the airport. Don't bring boring shoes you don't need.
4. Remember each character has a dialogue pattern. Your best friend or crazy aunt uses specific words, speaks distinctively, and responds predictably. For example, I once worked with a girl who never went to the bathroom, but the facilities' Some people mispronounce words while others use slang terms or swear when they speak. Depending on where they live, their status, and their first language, you might expect vastly different dialogue patterns. Someone who grew up in the UK, for example, may use a word that has a vastly different meaning in North America. A middle-aged woman who works in an office setting may speak differently than a 20-year-old man who works in a garage. Many of my characters are from Latino countries, so it's not uncommon for a little Spanish to get mixed into their conversations.
5. Don't overthink conversations. In real life, if you overthink a conversation, it tends to sound too stiff. The same goes for characters. Stay balanced and go with the flow when writing dialogue. See where it takes you. Sometimes, it might move the story in an unexpected direction, and as I always say, if you don't expect things to go a certain way, neither does the reader!
In the end, you want sharp dialogue that's dramatic and honest. Make the conversation pop!