I. More Description Is Always Good, As Long As It's Interesting
As a writer, you want to round out your world, fill it out in detail so that the reader can imagine it fully. Often, the writing can be made so much more vivid through patience - by laying out the setting, the characters, and the scene in detail. Instead of:
BAD: He watched the intruders from beneath the bed.
You could try:
BETTER: He crouched low, feeling the prickle of carpet press into his chin. His hair brushed the underside of the bed-frame and he imagined spiders. Boots came into view, shadowy in the dim light. He bit his lower 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.
At the same time, don't spend pages describing an ordinary household object, such as a toothbrush, unless there is something special about the toothbrush. But really, you can never have too much description. Often, a scene that takes up a page can be expanded into two, or even three pages, slowed down, and described in detail. Just make it original!
If you're going for the cluttered effect, nounsy description is almost always better than adjectival description – i.e., try to pack your description with lots of NOUNS, as opposed to lots of adjectives or adverbs. Multiple adjectives in front of a noun can actually detract from the power of the noun and should usually 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 red car.
See how the adjectives clutter up the writing? They distract from it, drawing your attention away from 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.