In fiction, the main character is often the first person we meet in the story. Given that the story is written from his/her point of view, how would you describe what they look like? The classical tricks (they look in a mirror or see their reflection in a lake) are not allowed (too traditional and boring). Do you have any other tips or tricks?
On one side of the spectrum, some ways of describing have the particularity that, instead of describing all of the character, they define them little by little.
I. You can highlight their body while they do something.
I gladly helped her take the book from the high shelf.
(Implying a tall character)
Even though the opening was large, I could only get my forearm through.
(So clearly it's a muscular character)
II. In the middle of a dialog, as a description:
"Alright, now, stop it", I interjected. Being burlier than him, I could afford to raise my voice.
III. Have someone make remarks about the characters.
"I had never noticed you had blue eyes", she said, leaning closer.
Of course, you can mix those. For instance, in that last example, you could add "I felt my face was getting as red as my hair" or something similar.
On the other side of the spectrum, you could use a technique that would be applied differently depending on the psychology of the character. For instance, you could have a very self conscious teenager reflect on their appearance; this approach would apply for a trendy character, too, although with a different feel (critically checking whether they look as they think they should, for instance). As far as I can tell, there are a few more character types that can have this technique easily applied, such as a narcissistic character, or simply one with high self esteem.
The "main thing" about this second approach is, depending on the characters' self esteem and general attitude towards life, and whatever number of factors, the general feel of the way they think about their appearance changes.
This isn't really any different than any other important information you want to get across early. Here's a few thoughts:
- A character considering how s/he might look to others is classic and pretty non-intrusive - e.g. "Somehow, people just see my blond hair and my perky smile, and never imagine such a cheerful, innocent-looking person might be a private detective who's awfully good at finding the skeletons in their closet." But this works particularly well for characters who feel that their (current) outward appearance is somehow odd or misleading, so YMMV.
- A character can always simply reflect on whether they look good enough for [[CHOOSE ONE: the meeting, the date, meeting his ultra-snobby friend, delivering a keynote address, impressing random passerby, not completely embarrassing oneself in front of random passerby, OTHER]]. But this could easily portray the character as somewhat vain, self-aware, or self-absorbed. Not always what you want.
- The key point to understand here is that, in order to justify explaining the character's appearance to your readers, you must find some point where the character himself needs to concern himself with his own appearance. Ask yourself: under what circumstances would that be? You can probably come up with circumstances which are very, very specific to your particular character.
- If you cannot find circumstances when your character would actually care about his own appearance, find circumstances under which some other character (somebody important to the story - not a random walk-on or Avon lady!) would care about his appearance. His mom before he leaves the house; his snobby friend dissing his clothes; a job interview where the prospective employer is clearly concerned that his scars imply a violent personality.
- If you cannot find circumstances where anybody would care about the character's specific appearance, or where they would make any significant difference, then it's worth considering if they're really worth describing. A book is not a movie; there's really no harm in letting readers form their own image of how the characters look - unless, for whatever reason, there are details that it's important for you to get across. But those details are probably the ones that are unusual (and hence, will be remarked upon), and/or that have significant effect on the character (and hence, you can find good situations to demonstrate them).
Hope this is helpful :)
Give the character a good reason to think about or comment on one key aspect of their own appearance. Perhaps the MC is proud of achieving something related to looks. Or jealous of another character. Or concerned about what some specific person might think. Maybe something has changed, by choice or otherwise. Or perhaps the character has to consider some physical attribute in order to make some decision. The important thing is to make it a strong reason that relates to the story.
Give another character a reason to comment. Maybe something has changed. Maybe the other character is envious. Or something.
Give the character some action that demonstrates or suggests physical attributes. Do they have to move the car seat back in order to fit behind the wheel? Or move it up to reach the pedals?
Leave something for the reader to fill in. Maybe leave all of it for the reader to fill in. I saw Michael Connolly speak once, and he said that there was some main character (maybe Harry Bosch, maybe some other) that he had never described.
One important point: If you are going to describe some distinctive feature, do it before the reader has filled in their own image. Learning on page 112 that the character is 6'5" tall can be jarring if the reader has imagined the character at average height.
All of the previous answers are good.
One technique I didn't see mentioned is that the reader can infer some of the POV character's looks when the POV character compares him or herself to other people, such as:
"Wow, that guy has even curlier hair than I do!"
"That guy must be loaded. I've been shopping big and tall shops since I was 16, and I know suits like that don't come cheap."
"Her mouth looks like mine before I got braces."
I subscribe to the "John Steinbeck school-of-thought" on character description, as set forth in his prologue to Sweet Tuesday:
I like a lot of talk in a book, and I don’t like to have nobody tell me what the guy that’s talking looks like. I want to figure out what he looks like from the way he talks.
Consequently, when I describe my characters I try to only include descriptions that are
- necessary for some plot point (e.g. referencing glasses on a character if his inability to see clearly without them is important);
- the cause of some character flaw or issue that is pertinent (e.g. a facial birthmark that creates shyness);
- the result of some necessary backstory the reader has or will be told about (e.g. a limp caused from a childhood fall); or
- is something unique enough that anyone meeting the character for the first time would obviously notice (e.g. Holden's red "people shooting hat" in Catcher in the Rye)