Description seems to be a topic of debate recently, everything from too much description to having no description at all.
THERE IS A BALANCE
Use descriptions like you use your shampoo: just enough to get the job done and only deep condition every once in a while.
THERE IS A THING AS TOO MUCH: I tried 3 times to read Lord of the Rings but could never get passed the first 20 pages. I was sick of that forest already and feared what else J.R.R Tolkien was going to fixate on and describe next.
I also read another book where the author spent a page and a half describing just the COLOR of her hair.
THERE IS A THING AS TOO LITTLE: I read a blog post that said readers don’t give a crap about what things look like because they are going to make up their own descriptions anyway. I don’t believe this one bit. I am a reader and I WANT to know what the character looks like. If I have to imagine what the character looks like then I might as well imagine what the town looks like and imagine what happens in the rest of the story, and then I might as well not read the story and read something else that doesn't make me work for those details.
Stephen King said: “Description should start with the writer and end with the reader.”
WHAT IS THE BALANCE?
ANSWER: WHEN IT IS RELEVANT AND FEELS NATURAL TO THE SCENE.
POOR USE: (Character is eating dinner and you randomly decide to describe what she's wearing): She wore high heels and a red dress.
A BETTER USE: She nearly fell off her high heels with how abruptly she stopped, the red skirt of her dress swishing around so it brushed his knee.
Why is the 2nd example better? Because it's more relevant and naturally flows into the scene connected to it. She’s running and has to stop. If you’ve ever worn high heels, it IS possible to fall off them (which is relevant to the moment of her “stopping abruptly”) and the motion of stopping would make the dress swing around and touch the man's knee. You are able to sneak in the color of the dress as well into that.
So what does Stephen King mean to start the description and let it end with the reader? I believe it is this: The dress is red. Let the reader fill in if it is made out of silk, lace, has beads. Unless the material of the dress is VITAL to some super story plot, you don’t need it. Now, mentioning how the dress dips low at the cleavage might be relevant if it allures a guy over to speak with red-wearing dress girl.
Make sure the description serves a purpose. Cleavage showing on the dress serves a purpose if something/someone reacts to it. Saying it is red serves a purpose in starting the description so the reader can finish it.
Can you still describe the material because you have a super-neat idea for a dress you want in your story? Sure. We writers love showing off our ideas. Why else would we write? Just still keep it natural and relevant to the scene. And don't OVER do it, either, Mr. Lord of the Rings!
I read THRONE OF GLASS by Sarah Maas and the character drove me bonkers. Every time she put on a new dress (every day) she would stand in front of the mirror, smile, and describe what the dress looked like. I could never see the point in knowing exactly what every dress looked like. And I didn’t think standing in front of a mirror to describe them felt RELEVANT to the scene. Why does character care what her dress looks like? No one else is looking at it. Standing in front of a mirror to describe oneself IS a natural thing to do but not relevant to the purpose of wearing a dress.
Now, standing in a ballroom and hoping the neck of your dress is not too low is relevant and natural to the scene (ballroom=description of dress. RELEVANT because people beside the character are looking at the dress and it may cause reactions for men to come over and interact with dress-wearing girl.)
Another thing to note is WHO is doing the describing. If you've read Wizard's First Rule, Terry Goodkind did this well. The particular instance I'm talking of is this: Rachel lives in a castle. She's been there for some time. We see very, very little description of the castle from her, just enough to see where she's walking or sitting. The description is simple - table, floor, bed. This is fitting because in these chapters we are in Rachel's point of view and she is so used to the castle that it would be uncharacteristic for her to describe it in detail. She might have described it in detail if this was her first day, but we don't meet her during her first day. We meet her after she's been there a while.
So then we go to Richard who has never been in Rachel's castle. He steps inside this same castle and description explodes as we are fed images of color and size. This is fitting, because he's never been here before. He goes on to describe vaulted ceilings with massive pillars ten people with linked hands wouldn't be able to reach around. The white and black marble floor, the meticulous garden outside. So while it would have felt natural and relevant to Rachel to describe the castle, Richard was the best fit to do so since it was his first visit.
Think of a place you have been to many times. You're used to it now. You don't see the colors or the size. Now you bring a friend to this place, and they stop and stare and "ooh" and "aah" at the same thing you've seen over and over. Same thing with characters.
IF YOU SKIMMED: Make sure description serves a purpose. Fit them in piece by piece as they become relevant to the moment and make sure it fits naturally in, and choose the best character to do this describing. Describing a dress while eating dinner is not relevant, but describing the dress while in a ballroom and a man comes over because he loves the color red, is. Start the description and let the reader finish it.