Let's talk dialogue. Dialogue is more than just listening in on a conversation. Dialogue tells you things about the characters that prose may not. Dialogue can set the pace of a story, moving it along. I've read a number of books lately where the dialogue doesn't rock. It feels (sounds) unnatural. It's pointless. It's not realistic...especially when we're talking YA. Sometimes the dialogue doesn't sound like kids talking.
Here are some of the dialogue traps I see:
1. Repeating people's names over and over.
2. Not using contractions.
3. Dialogue that doesn't move the story along.
So, how does one have rockin' dialogue? Let's look at some tips.
Listen to people talk. Really listen. While conversing, are they saying each other's names repeatedly? I'll bet they're not. I almost guarantee they're not. Unless they're stressing a point, or trying to get someone's attention, they're silent on the name-usage. When writing, do the same. Reserve the name-usage to those times when you're stressing a point or getting someone's attention. Also, keep note of people's body language when speaking; adding body language to your written dialogue helps makes it real.
Unless your character is speaking English as a second language, or your story is set in a time period (or world) where speech is more formal, people use contractions. If you go back to tip #1 and are listening to people talk, I'll, again, bet that they're using contractions. Leave the formality behind unless it has a purpose in your dialogue.
Avoid conversations that go nowhere. Dialogue is supposed to move a story along. Here's an instance where we have an exception to tip #1. Have you ever listened to two kids bicker about something? "Did not!" "Did too!" "Did not!" "Did too!" "Did not!" "Did too!" Okay, so that might be how a real conversation goes, but on paper? Bo-ring! It's pointless and goes nowhere and no one seriously wants to read that argument for half a page.
So, stop talking, and start listening and writing your rockin' dialogue!