What's this little guy going to say? That's up to you, the writer. You are going to decide on the words he'll utter within this bubble. We might see the bubble, or cloud, in a comic strip but in a short story or novel, the dialogue is written to stand alone.
Some writers agonize over writing dialogue while others write it effortlessly. Dialogue is meant to do several things:
1. Good dialogue will move your story along.
2. It will aid in showing rather than narrative telling.
3. It's a way to get information to the reader.
4. It's part of character development.
5. It shows relationships between characters
6. It breaks up long spates of pure narrattion
A few things to keep in mind when writing dialogue:
Contractions: People seldom speak in everyday conversation without using contractions. If that's the way conversation goes in real life, shouldn't your characters in a novel or short story speak in the same way? When I read a novel that has dialogue written in a formal way, in other words, no contractions, I can almost see the character standing straight as a toy soldier, arms at his sides and no expression on his face. The character begins to feel wooden, stilted, unemotional to me. One way to counteract that is to use contractions. Next time you're in a coffee shop or a waiting room where you're privy to other people's conversations, listen and learn. Do you hear formal speech in these everyday chats?
Actions within dialogue: Another way to keep from having toy soldier characters is to sprinkle actions into your dialogue. Let the character say something, follow with an action, or precede what is said with an action. It allows the reader to visulaize the scene along with the conversation. It also breaks up lengthy amounts of dialogue which can bog down the person reading it.
"Look at this, Tom. Do you know what I'm going to do with it?" Fred raised the paint-spattered hammer and waved it back and forth like a flag.
Fred picked up the paint-spattered hammer. "Do you see this, Tom? Do you know what I'm going to do with it?"
Tags: Lose the adverbs when writing tags in dialogue. We don't need to be told that Sally said something grumpily or nastily or hurriedly. he said or she said are quite sufficient. Use an action before or after if you want to convey an emotion in the speaker. She said, "Look at what we're doing, John." She slammed her book onto the kitchen table. Using more than the he said, she said tags distracts from what is actually being said. Remember that you do not need to have a tag after every sentence in dialogue. If it's a back and forth conversation, use the tags sparingly, the reader can generally figure out who is saying what. Give them that guidance in the opening lines, then carry on without them. Maybe sprinkle the tags in if it's a particularly long section of dialogue.
Complete sentences: It's not necessary to always use complete sentences in dialogue. Don't worry, your old English teacher will not appear out of nowhere and smack your hand. Once again, in normal conversation we often speak with phrases rather than complete sentences. Of course, you will have complete sentences for a great deal of your dialogue but toss in those phrases now and then. It will result in more natual conversation.
There's more to writing good dialogue than these few things that I've touched on today. Google the topic or find a book about writing dialogue. Read it, digest and apply to your own writing. Have fun making your characters speak to one another. I started doing it long ago when my friends and I played with paper dolls and made up stories about them along with lengthy conversations between the paper doll each of us held. Little did I know I was a writer in training!