W r i t i n g "T h e B i g P r i n t"
(with very special thanks to William Martell - visit his website at www.ScriptSecrets.Net )
1. THE WORD IS ACTION
Don't think of it as DESCRIPTION, think of it as ACTION.
Movement. Things happening.
Describing a stationary object is not only boring, it's probably not necessary.
If the scene heading says
INT. JOE'S LIVING ROOM - DAY,
the reader will imagine a sofa, some chairs, a TV, and most of the details.
We don't have to mention them. The screenwriter's job isn't to paint the whole picture,
but to give the essential dramatic details.
REMEMBER - You are writing MOTION pictures, and what you are describing is people and objects MOVING. So the first step is to remember you aren't describing THINGS; you are describing THINGS HAPPENING. When we use our words to paint pictures, we aren't painting still-lifes.
2. THE DEVIL IS IN THE DETAILS
There are times when INT. JOE'S LIVING ROOM - DAY is too generic. The reader needs additional information.
The trick is not to bore the reader by completely describing the living room.
Instead, find the one (or two) details which give us clue to the rest, and let the reader s imagination fill in the rest.
For example:
INT. JOE'S LOUNGE ROOM - DAY
Pizza boxes and empty beer cans litter the floor.
and
INT. JOE'S LOUNGE ROOM - DAY
A vase of fresh cut flowers on a doily atop the piano.
These are two very different lounge rooms. Imagine a lamp in the first room... it's different than the lamp you would imagine in the second room.
The carpet is different. The curtains are different. I imagine posters thumb tacked to the walls in the first room, and carefully framed fine art lithos in the second.
The key is to carefully choose a detail which implies other details. To find an example or metaphor which sums up the entire location.
That way you can describe an entire room in one short sentence. Notice that this gives us clues to character as well.
These are two VERY different Joes! 
3. HIDDEN DESCRIPTIONS
If we combine the first two steps, we come up with a third. The best place to hide a description is within action.
Instead of a boring, static image, give the reader an exciting bit of action and sneak in a little description along the way.
INT. JOE'S LIVING ROOM - DAY
Joe brushes away old pizza boxes, plops down on the sofa.
The reader is focusing on Joe, and doesn’t even notice you slip in the description of the living room. No static writing, no "still life" feel.
Economical writing which manages to do three things at the same time: Show things happening, describe the location, and illuminate character.
4. SMS IT!
Screenwriting is distilled writing. When it works best it works like poetry, evoking more than it actually says.
Novelists can spend pages describing something in minute detail (Proust wrote seven volumes on a fellow eating a cookie and remembering his past),
but we’ve got no more than 120 pages to get our entire story across.
Economical writing is important. And difficult. Instead of splashing words on the page, I have to pick each word carefully.
Relate the maximum message for the minimum price.
Screenwriting is similar to haiku, you have a limited number of words to paint your picture.
The trick is to choose words which IMPLY other words. Words that not only carry their own weight, but are strong enough to carry entire ideas and/or images.
If there's an art to screenwriting, it's knowing how to pick strong but simple words. Either while writing, or rewriting, I will take every sentence and try to find a more succinct way of relaying the information.
In first drafts I might use a half dozen words to do the same job a single word can do, or use extraneous words, or beat around the bush instead of finding a direct route to what I m trying to say. By imagining each sentence as part of a telegram (charged by the word) I decide exactly what I want to say and figure out the briefest way to say it.
5. CHOOSE YOUR WORDS CAREFULLY
The key to economical writing is word choice. I may splash words on the page for my first draft, but while rewriting I try to find the EXACT word to match the situation.
This accomplishes two things at once:
It creates quick, easy to read sentences... which have greater impact than their flabby counterparts.
When you write something like "Joe walks into the room", 'walks' is too generic.
There are probably a hundred synonyms for "walk", each describing a distinctive type of ambulation. Joe saunters in, strides in, struts in, strolls in, marches in, paces in, or bounces in; not only does this give us a specific type of walk, but adds to the action and character while removing boring overused words from your script.

6. ONCE MORE, WITH FEELING
Another trick is not to describe how something LOOKS, but how it FEELS. The Production Designer will decide what a room looks like, the Casting Director will decide what a character looks like... That leaves us describing ATTITUDES.
For example, instead of trying to describe an entire futuristic world, use these steps to give the reader a quick impression, allowing the reader's imagination to fill in the rest.
EXT. URBAN JUNGLE, 2019 AD -- EVENING
The wreckage of civilization. Crumbled buildings, burned out cars, streets pockmarked by war.
Downed power lines arc and spark on the street. This place makes Hell look like Beverly Hills...
Except the battered twisted metal sign reads "Beverly Hills". Night is falling. Fingers of shadow reaching out to grab anyone foolish enough to be in this part of town.
That's the only time the future world should be described in the script. Slug lines and action take it from here.
Between the arcing and sparking power lines and the fingers of shadow I show you how the future FEELS... frightening, ugly, dangerous.
7. MAKE IT POETIC
A little poetry goes a long ways. Using imagery, alliteration, homonyms and other forms of word play helps spice up your descriptions, but use them sparingly. Too much poetry reeks of "cutesy writing".
Writing asides to the reader is also "too cutsey".
Shane Black can get away with it, but chances are the rest of us can't. Remember, our job is to involve the reader in the story... Not jerk them out of it with wry asides or amusing allusions.
Your writing should be both interesting and invisible, which means the word play should service the script, not show what a clever writer you are.
8. AVOID TOO MUCH BLACK STUFF
An easy step for getting rid of dense "black stuff" is to remember the Four Line Rule. No passage of action should last longer than four lines. If you have a big action scene, which lasts a page or more... break it up with spaces!
Every four lines, put in a blank line. This instantly adds more "white stuff" to your script!
Another quick trick for long action passages is to have at least one line of dialogue on every page... even if it's just a character yelling "Watch out!" This breaks up the page, and gives the reader a break from reading actions described.
9. STYLE ON THE PAGE
The best way to make descriptions easy to read is to make them FUN to read. To create the excitement you envision on the screen, right on the page.
Develop your own personal style of writing action passages. Style breaks up the page and makes your writing distinctive.
Using sounds like "BLAM!" or "CLANG!"
Writing single sentence action blocks.
One.
Word.
Sentences.
Which.
Draw.
The.
Reader.
Down.
The.
Page.
Anything that makes the script more exciting to read, and involves the reader in the action. Experiment. After a few scripts, you will develop your own style and your own 'voice' in descriptions.
Developing a 'voice' is an important step in taking command of the page (more on that, later).

10. CHARACTER
Do you think you could completely describe a character in four words? Lawrence Kasdan managed that amazing feat in his script for "Body Heat". This is one of the best examples of clear, succinct writing I have ever read.
"Teddy Laurson, rock and roll arsonist."
Kasdan manages to convey Teddy's occupation and attitude which allows us to imagine details about everything from number of tattoos to hair length and personal grooming to wardrobe in ONLY FOUR WORDS!
If he can do it, so can you.
In the script, Heart Of Glass, Lt. Bobby Mazeppa is characterised as a "Beach boy homicide detective".
Your turn.
11. ACTIVE WORDS
A basic, but I've read dozens of scripts which would have been greatly improved had the writers stayed awake in their high school english classes when the teacher said: Use active verbs.
Joe doesn't TRY to sit on the sofa, he SITS on the sofa. In fact, he PLOPS DOWN on the sofa.
"Try" is a weasel verb... it takes the power from the active verb.
(Avoid "starts to" "begins to" and "ing" at the end of actions: "WALKS" is stronger than "walking".)
12. KILL THE WIDOWS!
In the wonderful world of typesetting, when the last word of a sentence carries over onto a new line of print it's called a widow . A single word which takes up an entire line of space. How wasteful! I always do a rewrite to kill all of the widows. If one or two words from the end of a sentence end up taking up an entire line, I rework the sentence until I can get it to fit entirely on one line. My goal is a widow-free script. Not only does this force me to choose the correct words, eliminate useless or fatty words, and write clear, concise sentences; it also trims my script, allowing room for more important elements. And the script looks cleaner on the page!
13. NO ANDS & BUTS!
The easiest two words to trim out of a sentence are AND and BUT. Usually these words are completely unnecessary. Cut them.
14. CONFIDENCE
Know what every sentence and every word means, and write clear enough so that anyone who reads your script understands what you have written. Write strong sentences and strong images.
Remember: You command the page. You control the words. You control the reader. This is writing with confidence.
A reader friend of mine frequently complains about writers who don't command the page. They seem unsure of what they're writing, filling their script with weasel verbs and beating around the bush with long, run on sentences. Don't fall into that trap. Know what you're going to write, write it. YOU are in control of your script.
15. PAGE TURNERS
Little cliff hangers at the end of your page which force the reader to turn to the next page. I have been known to add extra spaces or trim entire lines just to end a page on a moment of suspense.
If there is a moment where the hero is about to be killed but saves himself, I want the about to be killed at the end of one page so you have to turn the page and keep reading to get to the saves himself part.
In fact, I've even added artificial suspense to the end of a page to keep those pages turning.
I've saved the most important step for last: If you think your description could use a little trimming, take a chainsaw to it. Cut without mercy. Most of us are so in love with our own words that we don't cut enough.
Remember: LESS IS MORE!