Rule # 1 – “Limit the passive voice.” Replace the following verbs: am, is, are, was, were, be, being, been, with verbs that actually show the action or demonstrate the feeling. The key word here is REPLACE; don’t just eliminate the passive verb. Often while transforming the passive verbs into active verbs, the sentences have to be restructured and combined, thus creating a strong “showing” sentence.
Rule # 2 – Use the senses - sight, smell, taste, hearing (sounds), feeling (emotion) and touch - , to convey action or emotion. Don’t limit its use to one facet. For example, sight can encompass all the visual stimuli in your setting. It is not just what the character is seeing, but also the subtleties happening in the surroundings, and the actions and reactions of the other characters in the scene.
Rule # 3 – Because the medium for writers is THE PAGE, be aware of how the page looks and what the reader sees:
Sentences – Film uses music or lighting to create mood and tone; writers use sentences of varying length and structure to achieve the same. For example, consider the beat and intensity of a short, quick sentence versus a long languorous sentence.
Punctuation/spacing/other visual marks – These signal or cue different pauses and lapse in time, feelings and movement, introspection and dialogue, etc.
Dialogue/inner dialogue - The eye naturally gravitates to dialogue on the page, making its use and placement very important. Of equal importance are the tags or action beats that accompany it.
Rule # 4 – “Practice makes perfect.” One last piece of clichéd advice: The more these practices become part of the writer’s natural process and voice, the easier it will be to develop techniques to “show not tell.”