We are gathered here today to bathe in the light of The Revelation of script readers' terms and what they really mean. We The Readers are but seraphim in the heavenly production process and no one really listens to us anyway, but we *may* permit you through the Pearly Gates of options and deals or leave you outside to be devoured by the ravages of Time and perhaps Satan, who will let his evil hounds pick over your skeletal remains. Praise be to the Lords of Screenwriting (Lawrence Kasdan, Bill Martell, Danny Stack and all you other unsung Gods and Goddesses!):
SHOW IT, DON'T TELL IT: You've used 5 pages of dialogue with characters seated in one room? Characters chatting about "stuff" does not reveal character or push the story forward, it just makes a Reader want to strike you down with a bolt of lightning, or at least singe your butt with it. Ditto that for long speeches or hysterical and/or supposedly evil admissions of guilt: "I'm about to kill you now because..." ARGH. We don't live in Scooby Doo Land people, honest.
REVEAL CHARACTER: Saying what a character is wearing does not reveal character, it just does the costume peeps' job for them. Same for mentioning every single item in a room. Do you need all of it? Screenwriting is a series of judicious choices, "summing up" the sense of a room, place or person is always wiser than telling us every last detail. If nothing else, it means less work for YOU, the writer. This could mean another latte, walk in the park or roll in the hay for you Mortals instead of slaving over the PC. Think about it.
PUSH THE STORY FORWARD: What's the focus of every scene? You don't know what this particular scene's is? How does it fit in with your character's journey? You don't know? Then it's not pushing the story forward Scribo brothers and sisters. Lead us not into temptation of writing scenes with no focus, aaaaahhhhh... wait! I haven't finished!
EXTRANEOUS INFORMATION ACCESSIBLE ONLY TO THE READER: Are you using visuals, or writing a novel? The latter can only be appreciated by a Reader, not an audience. Similarly, if a character does NOT do something (like the scene description fave of "ignoring someone"!), how are we supposed to see this in terms of visuals? Let us all worship The ArchBishop of Red Pen.
DIRECTING FROM THE PAGE: Oh Brother, why are you telling us how this character speaks without it referring directly to the plot? Oh Sister, does it matter how the character stands, what she does with her hands, or how she smokes her cigarette? Join us in The Cult of Scene Description of Vagueness and Ambiguity, where you suggest stuff in the hope that directors and actors may grab your material and think it's their idea instead. Hallelujah.
OVERUSE OF PARENTHETICALS: So...what is this parenthetical for? Oh, right, how the actor says the line? Right, right. SEE ABOVE and then report to Purgatory. Paretheticals are ONLY for the most ambiguous of lines and/or to signify an accent or a different language. Never for (laughs), (sneers) etc, or actions like (checks his watch). NEVER! Thunderbolts and lightning, very very frightening...
NO CLEAR IMAGE (NCI): Remember: what you see is what you get, so if someone is "unconvinced", "madly in love", "undeterred", "nonchalant", "sceptical" and/or "resentful", then HOW DO WE KNOW THIS? Every Screenwriting Mortal must render actions as images, for again, in this script malarkey what you see is what you get. How about: "John raises a sceptical, unconvinced, nonchalant etc eyebrow"? But please don't raise too many eyebrows, fold too many arms, stir too many coffees, do too many high-fives or shake too many heads, that doesn't do it for us Readers either and we will still send your script to Hades (otherwise known as the "Out" tray).
IMPLIED NARRATOR: The Reader is the all-seeing eye and resents being reminded THIS IS A MOVIE, so any mentions of "We see/hear/follow/etc" is to be avoided in case of hysterical tantrums and loss of faith. The same goes for references to cameras and multiple shots. You want to ascend, right??
AVOID THE PRESENT CONTINUOUS: We're getting tense people, really tense... Why write "is" and "ing" when you can write less words in the present simple?? It's all about economy of words after all - plus we Readers need to get our seraphim wings refeathered at the end of the week, c'mon. And thou shalt never mix tenses (especially the past simple and present continuous) or die trying under the hooves of The Horsemen of The Writing Apocalypse (and it's coming baby!).
THOU SHALT KILL THE ADVERB: Whilst the "ly" word is very handy in normal life and I daresay for novel writing, shopping lists and other forms of creative writing, it is the enemy of The Mortal Screenwriter. Smite it down where you see it, only then may you triumph over its powerful brand of evil.