Too much of a good thing is never good, especially in animation. Over-animation is excessive animation that animators put into a scene. When animators over-animate, they give a character or an object unnecessary movements that ruin the animation’s purpose.
Here are 6 ways to avoid over-animating scenes:

1. Refer to the dialogue
A way to help you avoid over-animating is to get inside your character's head and think about how they would act in the situation you're animating.

2. Use real-life movements as references
Art often imitates life so when animating a character in a scene it is a great idea to shoot a reference video first.

3. Understand the character
Your character also has to feel and react the way people in real life do. Don't rush through the emotions and experiences of your character. Give your character time to think and process things and go from A to B.

4. Simplify your animation
Keeping it simple will make your character more lifelike and the scene more realistic.

5. Learn about acting from actors
Watch and learn from interview videos of famous actors discussing their acting techniques, realizations, posing, character staging, strengthening emotions, and other tips on analyzing movie characters.

6. Read books about acting for animators
Another good way to learn about how to do performance animation in your animated videos is to read books and articles about the topic such as "Acting for Animators" by Ed Hooks.

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