But if I did, it would be mostly about how communication and interaction between
characters isn't only about lines of dialogue, but tone of voice, body language,
facial expressions and all that stuff, and that most people don't stand face
to face, ramrod straight, hands flat against their thighs, and steadily exchange
information for five minutes and thirty-seven seconds sharp, after which they
go their separate ways.
And how, if you can't read your sentence out loud because you trip every four-syllabled word, for god's sake put down the thesaurus. For that matter, you're not allowed more than two pretty words per sentence because afterwards they start stealing each other's thunder.
(Run-on sentences are NOT verboten, but their usage is strictly regulated. Is your character babbling? Desperately out of breath? Are you stressing the hugeness and variety of someone's booty? (the piratey kind -- though, if you've got a character whose milk-shake demands a run-on sentence, I'm interested. ;3) Otherwise, cut it up, for god's sake. Here's a hint; people who try to read it out loud are turning blue. Dead readers are non-reviewing readers.)
Also, people interact with their settings; this means you should have a good idea of where everything is, or at least the main things -- size of the room, where's the furniture, is the tree at the front gate or at the end of the garden -- and possibly what it looks like; and don't randomly move it to other places. Shapeshifting rooms = rather freaky. (were-kitchens FTW.)
It's alright if you decide to let your reader imagine where everything is (in fact I'd rather have only one line or two about the mood and general impression the room gives off, and then a few descriptors dropped here and there amongst the action afterwards, than a snooze-worthy laundry list of thirty lines about the grain of the wood of the table and the market where the wine glasses were bought and the exact color of the linoleum and...) but it's different when you say that something is somewhere, and two minutes later, not only it has turned into something else and crawled five feet closer and to the left, but it has changed colors too! D: Imagine the poor character, exhausted, sprawling on his leather couch -- wait, no, it's an armchair -- a barstool! and he falls over.
On that note, people are not shapeshifters either. (unless they canonly are.) Yes, I mean you, miss can-bend-over-backwards-literally, and you, mister splits-are-easy(I-have-steel-hip-joints). (mister lubricating-anus is not invited to this convention.)
People only have two hands each. Really. Keep track of them when you lemon.
If you say that someone is taller than someone else, don't have other characters look down at him. If they want to give him a headpat, they'll have to reach up, etcetera. Keep physical differences -- not just eye color, hair length and dick size -- in mind. (If X is not actually taller than Y in canon, and this is not a few years and a few growth spurts later, HE BETTER STAY THAT WAY, just saying. The yaoi height rule needs to be shot point-blank range and buried in a shapeshifting cupboard which will then conveniently become an abandoned washing machine, and then we can dump it in the forest amongst its rusting brethen.)
And um, it's good if you find a writing trick that gives a great effect, but don't use it again and again and again like it's a whore and you just borrowed your daddy's credit card. Go buy yourself a riding crop, a vibrating egg, edible underwear, and try picking up people at the bar. Variety is the spice of fiction writing. Italicizing a word to stress it? Doesn't work when half of the whole fic is in italics. And there's a shortage of dots in Africa now. Think of all the little children who aren't allowed to trail off anymore, and must make do with semicolons instead.
Your fic is not prettier because your font is prettier. Your fic is masking its inadequacies and it would have masked them more convincingly if it had bought a red convertible to attract teenage girls instead, and now everyone will slam it for being sucky AND unreadable. Dark fonts on dark backgrounds deserve to die. Sparkly backgrounds should be drawn and quartered and then fed to the sharks.
Tiny, pretty fonts on sparkly backgrounds would probably bring PETA on our backs for shark mistreatment.
Think of the sharks. Keep your font under eye-gouging levels.
... oh hey, I guess I wrote it after all.
D;