Confession: my strongest suit in editing in proofreading. This probably stems from working too many shifts as a grammar tutor, but there it is. Chasing down commas is what I do (whether or not I’m supposed to).
However, where there’s strength in one area, there’s often weakness nearby. And my weakness is developmental editing. I often struggle with knowing how much to edit without losing the essence of the work. With this confession in mind, one of my internship supervisors recommended the book Developmental Editing: A Handbook for Freelancers, Authors, and Publishers by Scott Norton. He thought it would be a good introduction into the field and ended up reading it with me.