Have you ever seen the drawing of a pyramid of triangles in which you're supposed to count the number of triangles there are in the picture? Some people count the obvious smaller individual triangles, but miss the fact that the way the picture is drawn, there are bigger triangles throughout.
I think editing is similar. There are so many areas of editing, you may not be aware of where they show up and what you are doing when you do it. Let's look at a few instances.
You've made the decision to write a story. Boom! You've just done your first edit. You've made a choice in your life. You've edited your life and you will keep doing so every minute you take to develop that story. You edit when you create characters, giving them personalities. You edit when you create an outline (for those who do and those who don't still make decisions to move the story in a certain direction), deciding a timeline and the sequence of events.
Editing is not just done after you've completed the story, or when some publisher's editors splash it with colors highlighting the mistakes and suggested changes. Writers are editors and they have to be.
I love writers' critique groups and have been involved in three throughout the years. Each has had good and bad points in structure and operation but one of the problems I've seen in all of them is in regards to the writers themselves. A person brings Chapter One of a brand new story to the group for reading. The others listen then give their opinion on the strengths and weaknesses in the story. The person takes the story home and does a rewrite, brings it back to the group, hears more critique, then takes it home and does a rewrite…and the cycle continues. After a few rounds, someone will almost certainly suggest the person moves onto Chapter Two. Unfortunately, he/she cannot get past trying to perfect One. The story never gets written and either the person gives up or tries another story, falling into the same pattern.
Writers have to learn to work through each chapter until the story is completed. Sure, listen to the critiques, save the notes, keep in mind the suggestions, but keep writing something new until you've reached the end of the story. Then go back and rewrite.
Writers also have to know the rules. Grammar, punctuation, and of course spelling. Do not rely on spell check. You may not catch all of the mistakes (and believe me, you won't), but you want to present to the publisher/agent the best product you can create.
One of the fun ways to frustrate yourself is something my publisher and editors have agreed upon doing with each story we receive. When you think you've gone as far as you can with your self editing, go through and highlight every 'was', 'were', and 'that'. Then, go back through and eliminate all but the most necessary usages.
I've met authors who re-read scores of times and others who can whip out a decent product after only a few rewrites. There is no rule. You find what works for you. I wrote longhand and my first edit came when I transferred the pages to the computer. Then I'd print out the entire manuscript, grab a pen and a notebook and read through it marking corrections and scribbling changes for specific areas. I think it's where I learned a lot of my editing skills.
In early 2010, while waiting around for my story Night Shadows to run through the editing process, I exchanged emails with the senior editor and, to make a long story short, within about six weeks or so, I was hired as an editor. Now this surprised me, because I've had no official training, didn't take any college courses. I must have done very well on the 'test' story to satisfy the powers that be. Anyway, since that time, I have learned so much and I can pass on my knowledge to other authors.
I loathe working through the edits on my books. I've gone through several rounds of corrections and changes with Night Shadows, each one more excruciating than the last. Long hours until my brain goes fuzzy, but I'm learning. Editing others' material can be a horrendous job especially if the manuscript hasn't been polished by the author. However, it is a learning experience, because once you've read others' mistakes, you catch yourself making similar ones in your own projects.
And that's part of what makes writing so gosh darn fun.