Write well. Write often. Edit wisely.
What should an editor do for a writer?
There are different levels of editing, so the answer to the question of what an editor should do can be complex. But every editor can adhere to some standards—
Return edited manuscripts on time.
Keep abreast of current spellings (words change spelling with time) and technical jargon.
Read a manuscript more than once.
Refuse to hold back skills, knowledge, opinions. The client is paying for honesty and diligence.
Be frank. Don’t be swayed by a client’s talent or fame or subject knowledge.
Look up supposed facts—dates, events, history.
Point out sections that sound like gibberish.
Point out sections that sing.
Turn down an edit if the manuscript isn’t ready.
Suggest a different beginning, if warranted.
Suggest a different ending, if needed.
Recommend cutting characters, phrases, paragraphs, scenes, chapters, dialogue, description and events that don’t adhere to or enhance the story’s plot or tone.
Don’t just cut—make concrete suggestions for changing or adding to the story.
Learn genre requirements and expectations.
Be open to something new or unexpected.
Remember that it’s not your story.
Looking for the specifics of an editor’s job? Read Duties of an Editor/How Editors Help Writers.