One of the easiest places to fall into the telling trap is when you write about emotions. In general you want to avoid naming the emotion. If you do, then be sure to also provide a description of what behavior or feelings are accompanying it.
In real life, the man you just rear-ended rarely jumps out of his car yelling, “I’m so angry!” More likely he will show you by his behavior, body language, words, and tone.
What are some ways you know a family member is mad? Does he slam doors? Yell? Glare at you? You should give your readers those details and trust them to understand which emotion is being portrayed.
Every day we read cues from the world around us to indicate what other people are thinking. Let your readers do the same by allowing them to discern the emotion. It will be more powerful for them than if they are informed of what they should feel.
Father opened the door suddenly. He was angry. “Get out of here!” He yelled at Jenna.
The following rewrite of that scene uses colorful words to set the mood and to describe Father’s actions. As a result, it’s much scarier and allows us to feel like we are in the room with Jenna. Note that the words “angry” and “yelling” are not used, and yet it’s very clear Father is both.
The door banged open and Father loomed in the doorway. He glowered at Jenna, his face red. “Get out!”
Emotions can be revealed by creating a mood, in addition to describing body language. Words like “loomed” and “glowered” help add to the intimidation of this scene. Consider the connotation of the words you use, and it will help you choose ones that best enhance the mood you want to create.
Another benefit to showing emotions rather than naming them is that it reveals the personality of your character. Saying that Sarah is happy gives the reader very little information.
Is Sarah one to be happy by jumping up and down and screaming? Or is she more reserved, perhaps offering only a smile?
Is Damien destructive and loud when he is angry or quiet and seething? Does Miriam show her disapproval by making snide remarks or by pursing her lips?
Using the technique of showing will help you cement your characters’ personalities and make them more real to you and to your audience.