Cut long paragraphs into two or more shorter ones. If you write an op-ed that runs online, it is in your own self-interest to engage with commenters.
Be humorous, provided that your topic lends itself to humor. We especially like personal stories. This is especially true online. Or, look ahead to a holiday or anniversary a week from now that will provide a fresh news peg and enable editors to plan the story in advance.
In deciding on which point and sub-points to make, it helps if you know who is involved in the debate in question, especially if you think about the long-term goals you as an intellectual want to achieve by participating in that public debate. Here is an example of a recent op-ed I wrote for The Seattle Times.
Express your opinion, and then base it on factual, researched or first-hand information. Include a brief bio, along with your phone number, email address, and mailing address at the bottom if your article goes to a newspaper.