I have just finished reading Revision and Self-Editing by James Scott Bell. It was very informative and what I liked about this book was that he explained everything as simply as possible. I am not ashamed to say that I am rather simple minded.
Most of the book focuses on the basics of writing. Which was absolutely perfect for me, because he tells you what to do and what not to do. As well as what to look for when you edit. Not to mention all the handy writing exercises.
Basically, what I learned is that there is no formula to perfect editing. Your manuscript quality will depend on you, the author and you alone. All I can do is polish my manuscript to the best of my ability and hope it is good enough for who ever reads it.