I know, another editing post. Go on and roll your eyes. I'll be back to writing soon, and then this madness will cease. But for now...
Two quick disclaimers:
1. Take all writing rules with a grain of salt. You are the writer.
2. These are editing tips. The only red flag in a first draft is a blank page.
With that said, here are a few red-flag words. If you see these during revision (because I know you're not editing during your first draft) give them a second look, and make sure they really work.
When writing a scene, it should be obvious when something happens suddenly, without explicitly telling the reader.
"The wizard appeared suddenly."
If the wizard isn't there, and then he is, he appeared suddenly. No need to clarify.
This includes any form of "to be". Oftentimes, "to be" verbs signal the passive voice, which as a general rule weakens writing.
Which is stronger? "The sheep was killed." or "Mary killed the sheep."
Using forms of "to be" also limits opportunities to incorporate strong verbs into your sentences.
Here is an example from my current revision project:
"She was walking around the bar." vs. "She patrolled the bar."
Here is a great article with strategies to eliminate "to be" verbs.
This includes any modifiers specifying degree (really, so, etc.). Removing these words will tighten your prose and force you to imply degrees in other ways.
"She was very upset."
"She was upset."
"Her nails bit into her palms."
In the words of Mark Twain, "Substitute 'damn' every time you're inclined to write 'very;" your editor will delete it and the writing will be just as it should be."
Transitions such as "then" and "after" are usually redundant. The reader assumes scenes to be written in chronological order.
"The dog killed the bird. Then the dog ate the bird."
The reader will assume the eating to come after the killing without "Then."
Dialogue should not always be written as it is spoken. People tend to say, "Well, I did this," and "Look, this is the way it is." (Check out this post for more on dialogue.)
Readers, however, do not care about these introductory words and will likely find them irritating. Use of "well" should be limited to the dialogue of specific characters, whom the writer intends the reader to find irritating. Even then, use them sparingly.
I have probably removed more "that"s from my writing than any other word. It slips into drafts like a fungus.
"She knew that time was up."
"She knew time was up."
Personally, I find nine out of every ten uses of "that" to be unnecessary.
Words like "seem" and "appear" are some of the weakest in the English language. They undermine the narrator's authority.
"The girl seemed afraid."
"The girl was afraid."
Better yet (referencing red flag #2):
"The girl shuddered."
I'm sure you're noticing a pattern by now. Most of these red flag words undermine verb strength. The strength of your verbs is directly correlated to the impact and tightness of your prose.
Also "stuff" and any noun lacking specificity. These are placeholder nouns, used when you're not sure what to describe.
"He cleared the stuff from the couch."
"He cleared the stuffed animals and rattles from the couch."
Which tells more about the character and situation?
This also applies to pronouns, such as "it" and "they." Though pronouns are necessary to keep from cluttering your writing with repetitive nouns, they often become placeholders for ambiguous objects. Give them a second glance and make sure you can't replace them with a specific noun.
Overusing adverbs is one of the easiest ways to clutter your writing. Usually, adverbs can be replaced with action or metaphor.
"She walked slowly."
"She walked like her legs were iron."
As Stephen King said, "The road to hell is paved with adverbs."
Remember, none of these are hard and fast rules. They are red flags that deserve a second look during revision. View them as opportunities to make your writing stronger, but never sacrifice the integrity or your story simply to adhere to a revision "rule." If you ever doubt the necessity of marking through a sentence, think of this guidance:
"My most important piece of advice to all you would-be writers: When you write, try to leave out all the parts readers skip."