The Things I Learned in Fiction Class

More description is usually better, provided it's interesting

I. Flesh out your world

Description is great! As a writer, you want to round out your world in depth so your reader can fully imagine it. Let us know what your characters are hearing, seeing, smelling, tasting. What else is in the room? What especially stands out to them? Patient attention to detail will make your characters believable and your setting vibrant. 

Instead of:

BAD: Sam watched the intruder from beneath the bed.

You could try:

BETTER: The carpet prickled against Sam's chin. His hair brushed the underside of the bed-frame, and he shivered, imagining spiders. Boots came into view, shadowy in the dim light. Sam bit his lip to remind himself not to breathe, and a coppery taste filled his mouth. The boots clicked closer, and he saw that the heels were metal. The ankles were black, with a whisper of dust and walkway-grit around the edges.

The added description not only boosts the tension; it also tells us things about Sam, his surroundings, and the intruder. 

II. Lots of nouns is better than lots of adjectives

If you are going for the cluttered effect, try to pack your description with lots of nouns, instead of adjectives or adverbs. Multiple adjectives in front of a noun detracts from the power of the noun and should generally be avoided. 

Examples:

BAD: She dug her sharp fingernails deeper into the soapy, grunge-laden mass of thick tan, driving the sopping sponge deeper into the recesses of the old, dirty, red car.

See how the adjectives clutter the writing? They distract from the things we really care about: the nouns. 

BETTER: The sponge slid over the roof of the car, driving before it a wash of filth. Bubbles, blue and gray, bounced along the hood. Inside the car lay Kleenex, a pair of tennis shoes, books drained of color by the Florida sun, and an old rabbit leash with hearts across the collar.

Now it sounds cluttered, but in a different way – and this is more the way you want it to sound. There are still adjectives – don't get rid of those entirely! – but the nouns, the things, are what really drive the writing.

III. Make sure each sentence adds something new

Keep in mind the second half of ths chapter title. More description is better, provided it's interesting. This is key. 

Let's take a look at two more examples:

BAD: The chinchilla's fur was gray, soft and silky. I could not remember petting any animal that was as soft, or that had such smoothness to its fur, which was the color of the sky on a rainy day. Petting the chinchilla felt like petting a cloud: a silky, gray, chinchilla-shaped cloud. 

Here, the same idea is stated three times, in slightly different ways. Do we learn anything new in sentences 2 or 3? Not really. Is it annoying and repetitive? You betcha. 

BETTER: The chinchilla's fur was cloud-soft and silky. His color reminded me of the sky on a rainy day. He nuzzled my hand as I pet him, as though convinced I was hiding a treat. 

See how each sentence here relates its own idea? The key point here is: make sure each sentence adds something new to your description. Otherwise, your writing will feel bloated. 

One more set of examples, and then I'll let you go: 

BAD: I walked to the laundry basket, pulled out a t-shirt, and folded it. I picked out another t-shirt, and placed it on top of the first. I folded the socks next, and then the pants, and finally scooped out the underwear from the bottom of the laundry basket and placed that in my drawer. 

Unless your goal is to establish that your main character is a neat freak, this seems like an unnecessary (cough, boring) level of description for what is a pretty ordinary household activity. 

However, whether folding laundry is boring is all in how you spin it: 

BETTER: I had to do something with my hands, so I began folding Sarah's laundry, shirt by shirt, sock by sock. I don't know why I did it; it wasn't like she would be wearing these clothes again; she wasn't coming back. But something about the repetitive motion of layering cloth, the orderliness of it, soothed me. 

At the very bottom of the pile was the t-shirt I gave Sarah last Christmas, when she was home for winter break. It had a picture of Justin Bieber splashed across the front. I remembered Sarah's exasperation, the rolled eyes - A Bieber shirt? Really, Mom? - but she had put it on to humor me, even though it was a size too small. She had outgrown her Bieber phase, but I hadn't outgrown my memory of her with her high school friends, giggling in her room over posters and concerts. 

I clutched the shirt, pressed it into my face, and at last the tears came. 

Moral of the story: don't describe unimportant things to fill space. Try to make your description serve a purpose. That purpose can be making your world bright and vivid in our eyes, or advancing the story in some critical way.