You won't produce a perfect, finished work on the first draft. Let that idea go. And you want to put your best work out there, whether you're trying to entice an agent or hoping for self-publishing success. Even if you hire an editor (and we suggest that you do so), you are your own first line of defense. So here are 10 solid tips for editing your own work:
1) Don't be negative. Instead of saying what something isn't, show what it is. For example, the way that first sentence should have been written is, "Be positive." Instead of saying, "Don't make these mistakes," write, "Avoid these mistakes." Bonus: Use active voice, active verbs, rather than passive construction.
2) Avoid repetition. Examples: exact same; basic necessities; boat marina; restaurant chef; brand new. Bonus: Use "who" to refer to people, "that" to refer to situations (i.e., "People who like to write," not "People that like to write.")
3) Avoid "very", "really," and other -ly words (adverbs). They steal energy from your verbs without adding description. He doesn't move very quickly, he hurries. She isn't really scared, she's terrified. Bonus: Participles aren't your friends. Don't write "They were deciding to..." (instead, "They decided to..." or if you want to be in the midst of the decision-making, "They discussed...).
4) Don't use a $1 word when a 10-cent one will do. Clarity is the essence of communication. If your reader has to go to the dictionary too often, then your writing has jarred them out of the story. Bonus: Jargon only works in small doses to lend verisimilitude (i.e., in a police procedural).
5) Avoid starting sentences with "there was” or “there were.” Rewrite the sentence to use an active verb and specific language. (i.e., rather than "There were six people waiting in the jury room," try "Six people waited in the jury room....") Bonus: Use contractions, especially in dialogue. The android, Data, on Star Trek: The Next Generation never mastered them, so his speech remained inhuman. Don't be Data.
Bonus) Know your tells. Everyone has a way of saying things, words they use more often than others. Watch out for patterns in your writing and over-used words. (I have a tendency for characters to nod, and over-use "look" in all its meanings.) Don't make all the girls in your story have the same hair or eyes, for instance.