1) Make the scene three-dimensional in the reader’s mind

There is Flaubert’s rule that you need three particular things in the room for the room to become three-dimensional in the reader’s mind.  So that if we establish this box of Kleenex, that bottle, and that lamp — not in one sentence, but over a few paragraphs — the room will pop into three-dimensional space.
–Lawrence Weschler, in The New New Journalism (2005)

2) Find the thing that isn’t typical

I remember reading somewhere in Hemingway—I think it’s in one of his stories—where a character who’s a writer is talking to his son, and he tells the kid a trick about description. He says: when you go to a Cuban marketplace, your first instinct is to catalog everything you see, especially the stuff that’s typical of a third-world market place. But his advice is to find the one thing that isn’t typical. The example he uses is of a cockfight, where one of the handlers is literally putting the chicken’s head in his mouth and blowing into the chicken, which—not surprisingly—enrages the chicken. And when you get that one odd detail, the whole marketplace will spring up in the reader’s mind. All of the commonplace things—you know, the stalls, the dirt path, the dead pigs and so on—will be supplied by your mind.
–George Saunders, “Loose in the Real World,” World Hum, September 28, 2007

3) Remember to draw on all five senses

Most of us rely so heavily on eyesight to inform our experiences that we make the same mistake in our writing — ignoring the other four senses, lumping them together, misfiling sounds and smells into the see and go bins.  I “saw” the Black Sea. (But what did it feel like?) I “went” to the Djoudj Bird Sanctuary. (How did it sound?)
–Lavinia Spalding, Writing Away (2009)

4) Ancillary details help deepen the reader’s attention

The protagonist in The Professor and The Madman cuts off his own penis and throws it into the fire. When I discovered this in an archive in the lunatic asylum where WC Minor was incarcerated, I was exultant: I knew his work rate had fallen off very badly and we didn’t know quite know why. That evening I was going by train down to London and I met two elderly female lexicographers waiting for the train, and I said, “Oh, I have this wonderful story to tell you.” So there’s the first thing — to get them to anticipate the story and herd them onto the train. And the train is, you know, an open-plan train full of businessmen who had been selling motor cars in Oxford or something that day and I was telling the story, and I’ve got this voice which sort of tends to carry a bit, and I was laying it on with a trowel, you know, talking about how he had used the very same knife that he had used to cut out the 3-by-5 cards to send his quotations up to the dictionary, how he had sharpened that on a whetstone for three nights and how, because he was a surgeon and knew what to do, he had tied a string around the base of his member to act as a ligature and then cut it off with one great motion. And from all these men came this gasp of horror and the crossing of hundreds of pairs of legs. But then there was this even more wonderful moment when these two women who were lexicographers made no response at all but just stared at me. You could see the lexicographical gears going round and round in their heads and then, I swear to this day they said it in unison, they said, “Otopeotomy.” And then one of them said, “Peotomy, which is the amputation of the penis. I believe I’m right, Elizabeth, aren’t I? It does exist in the second edition of the OED, but I’m fairly sure, do correct me if I’m wrong, Elizabeth, but I think otopeotomy, doing it to yourself, is actually a neologism. And Mr. Winchester, if you can put it in an illustrative context in your book, we’ll put it in the third edition.” So, the point I’m trying to make is get those ancillary details and you’ll hold their attention.
–Simon Winchester, interviewed by Don George for LonelyPlanet.com (2003)

5) Description is colored by the person who is doing the noticing

Description must work for its place. It can’t be simply ornamental. It ­usually works best if it has a human element; it is more effective if it comes from an implied viewpoint, rather than from the eye of God. If description is colored by the viewpoint of the character who is doing the noticing, it becomes, in effect, part of character definition and part of the action.
–Hilary Mantel, “Ten rules for writing fiction,” The Guardian, February 20, 2010

6) Emotional notes create different harmonies

No telephone merely rings. We cocreate the sound that calls to us. Anticipating his lover, a man will approach the ringing phone with pleasure; the ringing during dinner — perhaps a telemarketer’s call — sounds abrasive, ugly; and the ringing that wakes us in the night is tinged with our confusion and dread. Each ring sounds different — we provide the emotional notes that create different harmonics.
–Philip Graham, from Now Write! Nonfiction (2006)

7) Paint a concrete picture; don’t just state facts

At a Lewd Acts on Child crime scene, Martinez’s partner, Officer Brown, writes, “The Victim sustained multiple injuries.” Officer Martinez would tell us, “The Baby was bleeding from three orifices.” There’s a world of difference here. Brown gives us a victim; Martinez gives us a baby. Brown offers a fact; Martinez paints a picture. Brown’s statement moves us forward; Martinez’s makes us stop dead and envision the horrific crime that caused such injuries. Both statements are neutral on the surface, but the specificity of Martinez’s language makes the reader see and feel.  …From a reader’s perspective, his incident reports are deeply satisfying. They engage us emotionally; vest us in the events he describes, and in the teller. They’re narratives that hint at larger truths—about Martinez himself and the South Central universe he polices. They’re deliberately authored and inflected, rife with the dissonances that make us think. They reverberate beyond the time it takes to read them. They offer a way to understand the world.  They feel suspiciously like stories.
–Ellen Collett, “Inflection & the Narrative Voice,” AWP Chronicle, Dec 2010