1) Thank the author for the blog post and then write the rest of the comment for the broader audience. If you don’t have something well thought out, then just leave it at that.
2) Indicate whether you agree or disagree and why. Often, I have no idea what the comment is saying. Keep it simple.
3) Provide no more than one or two things that you agree or disagree with the blog post to enhance others' understanding.
4) Keep it polite and be respectful of the blogger no matter how much you disagree with it. Is you want to rebut it, then write your own blog.
Remember, you are commenting, not trying to win an argument with the blogger or other readers. Meanwhile, when commenting on a blog post, keep it simple, relevant and short so we know what you are saying and can easily exchange our views.
Jay Oza is a founder and principal innovation development consultant at 5ToolGroup, a company that specializes in helping startups and established firms bring innovation to market within 90 days through our unique 5Tool Methodology that integrates sales, marketing, partnerships, customer development and agile/lean methodology to enable frugal or ("Jugaad") innovation. We believe that to succeed today, you have to continuously look for ways do lot more with lot less. This is the only way to win today.