To show emotion when trying to express strong feeling or drama it works very well to use similes and metaphors.
This is an example of a simile : He was as quiet as a mouse when sneaking to bed.
A simile is a comparison that usually uses the words as and like. The form of like used is the form that means similar to. When you say similar to and simile they both sound alike. That can help one memorize the meaning.
A metaphor isn't a comparison, but actually states that something is something else. Here is an example : The spider was a black jewel reflecting the sunlight.
The type of word that one would use in a metaphor is to be. That includes was, is, has been, and will be.
This is an example on using adjectives, metaphors, and similes to add emotion to your writing : My heart was the dancing sun. Bright, joyful, and happy. My dreams were as complete as a freshly cooked pie that hasn't been disturbed. My glorious and marvelous purpose in life had been fulfilled, though I had dozens and dozens more years to live.
An emotion doesn't have to be sad but can be joyful, like my example showed you. you probably also sense a feeling of pure joy, though you don't know the cause. The cause could be learning how to tie your shoe, or getting an A on your test. The main goal when adding emotion is to give the feeling of the emotion the author chooses and make the reader feel it.
To conclude on emotion I will write what you should think about for each emotion.
Angriness - Describe how horrible the person feels and describe what that person feels like doing to the cause of the angriness. Use a thesaurus and look up synonyms for angry. Some synonyms are enraged, fierce, fiery, irate, ragng, fuming, infuriated, furious, wrathful, stormy, indignant, cross, vexed, resentful, irritated, bitter, ferocious, offended, sullen, hateful, annoyed, huffy, hostile, rabid, "flown off the haandle", mad, "up in the air", "hot under the collar", boiling, "steamed up", "at the boiling point", "all worked up" (I give all credit for the synonyms to my Webster's New World Thesaurus by Charlton Laird)
Happiness - Compare happiness with a joyful object of person. Metaphors work effectivley on happiness as well as sadness. Once again look up synonyms.
Sadness - Describe with plentiful adjectives about the sadness. Think of a result of sadness (an action that the sad person does). Use metaphors to help the drama come to life. Looking up synonyms (syn.) help for all emotions.
Excitedness - How the wonder struck the person or thing (like the surprise party struck her with surprise, etc.) Is it good or bad excitedness? What causes the excitedness? Even in a fiction story you can use fantasy events as feelings (soaring through the skies, etc.)
I hope that this guide is helpful to you!