Thanks to NaNoWriMo, writers around the planet wrote 3,073,723,493 new words during the month of November 2011. If you divide that by 50K, that's more than sixty-one thousand novels. That just blows my mind.
Most of these new novels will probably need to be edited and corrected, and will have significant portions that require rewriting and revising. Which is why we should probably designate the months of December, January and February as The International Fix the Book Festival (in reality there is a NaNoEdMo, which takes place in March, details for which you can read about here.)
As soon as I'm finished writing a novel, I do take some time off to recharge before I do my book-length edit. These days I try to give myself at least two weeks downtime, but if that's not possible I shoot for a minimum of 48 hours. During my downtime I devote myself to making my writer side part ways with the book. Which means I don't look it, I don't check anything, and I definitely try very hard not to think about it.
The break between writing and editing is important to my process, not just to refill the well but to put a little distance between me and a story I've been living with and working on daily for weeks and months and even years. It also allows me to shift from storyteller to self-editor, also imperative if I'm going to edit as objectively as I can.
I usually have no problem separating from a book once I've wrapped up the writing end of it. Crossing the finish line is a good feeling most of the time -- there's a lot of satisfaction to be had simply by getting the job done -- but occasionally that feeling doesn't happen, at which point it's more important than ever that I give myself some time away from the novel.
99% of the time I think these negative feelings are caused by doubt or worry over another factor, like concern over the quality of the writing, the actual chances of selling it, and/or what everyone will think about it (that one regularly strikes first-time novelists.) For pros it can be caused by something like a new editor, or a change of publishers, or the first book in a new series.
When it happens to me, I start to question myself, and of course I blame the writing because that's right in front of me and feels like the source of the negativity. I start having these radical urges that tell me to gut the manuscript, or start over, or cancel the contract, or give up Publishing altogether and go into the quilt business.
This is another reason why I think that break between writing and editing is so necessary. Post-novel, writers can at times be like little kids suffering from separation anxiety. Some of us get scared and don't want to let go.
Once I feel like my emotions aren't going to drag me and my manuscript under the bed and keep us there until next Christmas, I set up an editing schedule. Because I do a complete pass of the full manuscript, I divide the work into chapters starting at the beginning. Unless I'm under a severe time crunch, I generally don't edit more than three or four chapters a day, nor do I edit less than two. Editing too much of the book in one session can cause me to rush the reading and miss things I should have caught; editing too little of the book makes me more prone to linger and overthink and second-guess.
A few years back I wrote a blog post that detailed in general how I edit, and that really hasn't changed. I think these days I'm a better proof-reader, simply because I've spent so many years proofing manuscripts. I'll still use spell-check once I've finished typing in all my corrections, but my days of multiple spell-checks of any manuscript are over (and this is primarily due to Microsoft making it too wonky to be useful.)
All of this is not to say that you have to edit your novel as I do mine. Just as writing is a process unique to the writer, so is editing. I'd try any advice that you think might work well for you, but don't be afraid to evolve your own approach, either. You may find yourself editing happily ever after each book you write, and that's the sort of HEA we all want.
Related links: Carrie Kei Heim Binas's blog post on using Wordle as an editing tool ~ Do You Copy? Tips on Copy Editing Your Own Work by Janice Hardy ~ Proofreading and Editing Tips: a compilation of advice from experienced proofreaders and editors