I am an editor and writer who has worked for over seven years as deputy editor of Good Reading, Australia’s only magazine about books and reading pitched at the general reader. If I'm not working on the words produced by my own brain, I'm often finessing the words that flow out of other people's heads
Editors, like people in any field, have their favourite subtopics and specialties. I'm particularly interested in vocabulary, but I'm also fascinated by grammar. Studying English grammar doesn't have to be the intimidating prospect that it might at first appear to be. Knowing more about grammar will not only make you a better writer, but it will also – eventually – fascinate you and make you more confident in expressing yourself.
That said, to really know English grammar – at the very least, for example, to be able to distinguish an emphatic pronoun from a reflexive one (out of context they look identical) – takes a serious level of dedication and commitment in this era when grammar has been relegated into oblivion on all curriculums, in both schools and universities. (If you want an easy-to-read but comprehensive introduction, try  Complete English Grammar Rules , published by Farlex International. Each chapter ends with a quiz, which is great in helping to ensure that your newly acquired grammar knowledge is retained.)
When editing text, an editor needs be sure, for example, that the author is not using the word specious when spurious might have been the more appropriate word, or watchword when byword would have made more sense. Many of us often think we know the meaning of a word when we really don't, and we often haven't bothered to look up the actual meaning of these thorny little tricksters that can snag the unwary. The word prevaricate, I've noticed lately, has started to appear where procrastinate was clearly intended, and although the two words might look similar, they aren't synonyms.
Good writing doesn’t have to be filled with obscure and pretentious words to make an impact, but it should get your message across with a minimum of ambiguity and confusion (unless you're deliberately aiming for ambiguity). Skilful editing involves following what might sometimes seem like pointlessly persnickety and arbitrary rules, but those rules can be broken; they just need to be broken consciously and not because of ignorance.
A good editor constantly undergoes education, whether that involves formal courses or a program of self-administered instruction. Every couple of years I re-read Strunk and White’s The Elements of Style, William Zinsser's On Writing Well and Roy Peter Clark's Writing Tools, in addition to reading new books on the topics of editing, grammar and style. I'm also deeply interested in the lost art of rhetoric and the impact it can add to writing. See this book for a great introduction to the subject –  You Talkin’ to Me?: Rhetoric from Aristotle to Obama .
Other things I’m interested in include