In the great majority of unpublished manuscripts I read, character description is handled in a very predictable way. Say our point of view character is meeting someone new. It's natural that the writer wants readers to know what this person looks like, and that's not wrong at all. But 80% of the time, the very next paragraph will be a block of description. Example:
I paused in the hall as she walked toward me.
Blond hair swung to her shoulders, framing a sharp face and even sharper blue eyes. Her eyes were almond-shaped with long, dark eyelashes. Her skin was pale, but her smile was bright and turned her expression from icy to welcoming. She was taller than me, even in her flats, and thin. Even with her all natural, no cosmetics style, she was strikingly beautiful.
"Hi," I said, and held out my hand.
Not everything about this paragraph is bad, but it has a lot of issues. The first (and not the biggest) issue is that it's predictable. A lot of writers chose to stop when we meet a new character and launch into a description. This one, in fact, is a lot shorter than most of the character descriptions I've seen. There are a lot of creative and unique ways to help the readers see your characters, and jumping to the most obvious option isn't always the best choice.
Another more serious reason this method for describing doesn't work well is that it stops the action. No one is doing anything in those sentences. If this were a movie, the characters would be standing there staring at each other. On the page, what's happening is the writer lifted the character up onto a pedestal and directed us to walk around her in a circle and make note of all her traits. It's boring and disruptive, and it slows the pace of the scene.
A side issue here is that this block of description often happens even when the POV character already knows the person, like a sister or friend who is appearing in the story for the first time. There's very little reason for the character to stop and think about her friend's hair and eye color at that moment, so it's even more disruptive than when the character is meeting a new person.
The final reason this method doesn't usually work well is that details presented that way are lifeless. We're being told facts about a character, and it's a long list of facts all lumped together. Readers are going to forget most of them in a few pages, and they won't make much of an impact because in the moment, those details didn't carry much weight.
So. If you're not going to describe characters that way, what else can you do?
A lot. So, so much. Here are some tips and tricks and things I love seeing:
1) Get rid of the "standing there and staring" effect. If you watch people, you'll notice they're almost never standing there staring into space (except me, in the morning). They're unloading vehicles, cleaning off desks, waiting on tables, herding kids out the door, arguing with someone on the phone, playing basketball with friends in the park, etc. Put your characters in motion, and you open up all kinds of opportunities for describing beyond the basics. When we first see characters, whether the main character knows them already or not, have them doing something. It gives the scene action, it can show us so much about who this person is and what they do, and it reframes what you can do with the moment. So put those characters in motion. Bonus tip: romance writers, motion is way sexy. Forget muscle and curves. How a girl or guy moves can show so much confidence, competence, and intelligence. Give us more of that!
2) Once we meet a new character (and said character is DOING something) feel free to use the moment to give us a line or two to help visualize that person. But take note of the specifics there. Use a line or two, not a paragraph. Two sentences can even drag down the moment if they're long ones. And notice I said "visualize the character." Writers often run to hair, height, eye color, and weight for those quick descriptions, but those don't really help readers visualize. That tells me almost nothing about this person is, and it's actually pretty difficult to visualize. When I think about my friends, those descriptors aren't the ones that come to mind. Posture, persona, and mannerisms are often more impacting than height and hair color. What's most impacting in that moment about the person? If it's a little sister, it may be that her shirt is on backwards and she's wearing your shoes again. If it's the first time the MC is meeting this character, it may be confidence or shyness. Those kinds of things are what people tend to notice first, and they tell us more than driver's license details.
3) Once we have a few specific details that personalize the character and they're in motion in an active scene, go crazy giving life to the bodies and personalities of these characters. Is she tall? Don't tell us that, show it by making the detail impact the scene. Maybe your character has trouble keeping up with her long stride. Is he a particularly buff guy? Show it off by having him do something active. (Again, motion=sexy!) Smart, shy, confident, unobservant-- get these traits to impact the scene, even in a small way, and you'll have impacting first moments for your characters. When you're describing physical details, it can be harder to have hair color or weight impact the scene, and we do need to know those things if it's an important character. I love seeing these details integrated naturally, at a point when the character would notice it. For example, the height=long stride example. Or else, with hair color, perhaps the girl is pulling her frizzy blond curls into a ponytail. Clothing style can even be handled this way, because how a character wears her clothing can tell us even more about her than what kind of clothes she's wearing. Give the detail life and motion when you can, and if there's not a great moment for it right then, save it and don't force it.
4) We don't need to know everything at once, right up front. In fact, it's better that we don't, because we then avoid the laundry list of facts. If eye color doesn't matter right then, rest assured your readers will believe the character has eyes unless you tell them differently, and you can come back to it in a scene where it matters or fits better. Keep describing through motion and details that impact the scene in each chapter, sprinkle in new details, and reinforce the ones already shown by coming back to it when it fits. This will help give your characters constant physical presence and enable your readers to solidly visualize them in each scene.
5) Finally, it's much easier to make those details impact the scene and much easier to keep your characters in motion when they are realistic in how they interact with the world. We text, turn up the music, fill our water bottles, jingle our keys, tap our fingers on the table, carry things important to us, fiddle with pencils and rubber bands, etc. Give your characters little things they can do and play with to show bits of their personality and mood. It adds a fun, realistic texture to the scene, because a) it's action and b) we all do it. It also enables you to get away from running hands through hair, biting lips, and raising eyebrows when you need an action beat for a scene.
The other half of making your characters interact with the world is in using their entire body. I'd guess that 80% of character motion and description I see focuses on arms, head, and shoulders. Be sure to go below the shoulders with motion and detail. Your characters should need their entire body, and normally a fully realized character should need it in every scene. Beyond just walking and wearing cute jeans, have them involve their lower halves in the scene. Characters can stub their toes, tap their feet, cross their legs, wear anklets and toe rings, paint toe nails, kick cans, hate how her knees look, think he has hobbit feet, etc. Make the characters use their whole body to interact with the world, both in details and habits.
The awesome thing about character description is that it's not a market issue and it's not about rising out of the slush pile. It's about giving your characters a lifelike physical presence that readers can connect with, remember, and enjoy.
Any questions? Ask them below, and I'll answer if I can!