When you edit, resist the temptation to make corrections as soon as you spot flaws. Instead, edit in three steps because each time you read it, you should focus on something different.
This process does not apply to a two-sentence email about grabbing a beer after work. But if the document is a page or longer, or if it is an important message even if it is short, then take the time to edit carefully. Too often, people can’t help themselves when they begin to edit, so they start correcting mistakes and revising sentences as soon as they see things that need to be changed. But they are trying to accomplish too much at once.
The first time through is only an overview. You want to be sure that the body supports the opening paragraph, that the entire message makes sense, and there is nothing obviously missing or disorganized.
In the second reading, you narrow your focus by zooming in on paragraphs and sentences. Are paragraphs coherently wrapped around one main idea? Do paragraphs and sentences flow smoothly from one to the next? Are sentences efficiently written or flabby with extra words? Is the language clear, or is the message littered with buzzwords and technical words?
The third reading is the line-by-line editing we call proofreading, where you look for mistakes of grammar, punctuation, and style. You can’t be scrutinizing the copy for these the first time you read because you have bigger, more important issues to pay attention to. But you will be so focused on wondering if it should be a comma or a semicolon, or second-guessing yourself on a usage issue, that you will not notice that the entire sentence is in the wrong place.
Another suggestion is to print the document, at least for the third reading, preferably earlier. It will appear different to your eye, because the resolution of ink on paper is sharper than pixels on a screen, so you will notice things in a “hard copy” that you won’t notice on the screen.