Dear reader, the difference between editing and proofreading (not many make the distinction) is that editing is the overall quality of the writing: language use is thoughtful and has an impact (each draft is better); expressions (metaphor and simile) are clearer than before; errors and in inconsistencies are removed (errors by reading aloud, inconsistencies by text highlights and listing); maximum effect with minimum words. Proofreading is more tedious and very important for the overall readability of your text. Read carefully for spelling, grammar, verb tense, and typing mistakes to make a professional impression on the reader. Be consistent with language (high, medium, low--think of Falstaff and Hamlet for the difference); always make good writing into better and to best if you can (good is adequate and better pulls your reader into the text and best make your reader think about your ideas); be certain that your text looks good (same size and font) on the page and is ready to read by the public (includes page formatting that meets standards).
Those are the basics but important enough to spend a good deal of time on them. I use some tricks to be certain that I meet standards that we should all have in proofreading and editing. First, I do a global check. I read each paragraph to be certain of names, transitions, and descriptions. Then, I read the paragraphs as stand-alone text to test if it tells part of the story or is just filler or commentary. If they seem incomplete or clunky, spend as much time as required to rewrite. This goes for all paragraphs (sometimes I do this backward so that the plot does not interfere with the process). Second, I am very careful about word choice. The wrong word will connotate the wrong sympathy. For example, the difference between "idle" and "lazy" is at least three steps apart. Don't put up with "idle or lazy" words when a different one will say exactly what you want to say. For a second example, you have all heard the imploration to omit "There are..that" combinations. The reason is that There is in the subject position of the sentence and makes no sense. That is indifferent in its purpose so rewrite the sentence (replace There with the subject and That should disappear).
My next discussion will be on sentencing. You would think writing a sentence would be simple; we do it all the time. The difference between a sentence in a letter and one in literature is a rowboat next to a yacht. After all, the entirety of your story is a series of sentences. Make them effective and memorable and the story will be memorable. Hope this was a good reminder, Steven Sweek