Saw the following opinion piece in yesterday's Washington Post. Though the advice is ancient, it still holds true, for letters to the editor and blog posts, too.
Washington Post
Letters to the Editor Free for All
October 29, 2009
19th-century writing tips that still serve in 2009
As an amateur writer of local history, I recently came across an April 5, 1896, piece in The Post, "The Post's Amateur Writers." Its advice for letters to the editor is as good now as it was then.
First, "Do not make your articles so long." An overlong piece gets tedious to read and crowds out space that other writers could appear in.
Next, "Go over them carefully, eliminate all unnecessary words, keep a careful eye upon spelling, and be sure your sentences are coherent and sensible." In particular, "you will find in all probability that misspelled words lower your chances for acceptances."
Also, "It will not be inadvisable for the majority of you to keep strict account of your paragraphs." Don't turn off the reader with "a solid page of cramped, illegible writing." Note: The "not be inadvisable" is too wordy. Also, it's a double negative, something a writer should seldom, if ever, use.
Finally, "Don't strain after subjects. Write about what interests you, and what happens to you, and all will lend an attractive and friendly ear." Perhaps the writer meant "attentive" rather than "attractive." Here is some related advice all my own: Don't try to copy or make up a writing style. Just write on your own, and you will find you have a style all your own.
I have said all I need to say on this subject, so I will keep this short and stop here.
John Lockwood, Washington