Writing blog posts and comments on blogs is actually very simple. The basic guidelines: keep your copy lively, factual, tight, clear, short and search engine optimized.
Here are basic blog style guidelines to follow:
Adopt a direct style. Declarative sentences are good. Web readers demand them.
Link like crazy. One thing that distinguishes blog posts from dead-tree journalism is that bloggers link prodigiously.
Link to any other blog or Web site you mention. Link to articles, books, products, bios, explanatory materials on other sites and anything you mention in your blog.
Always link to information that clarifies or gives background on information and opinions in your post.
Write less. Omit all unnecessary words. The best advice I ever got about writing was from my first boss, the late "press agent" Leo Miller, who taught me a game to play with sentences. He'd keep taking out words until removing one more word destroyed the meaning of the sentence.
For example: He'd take out words until removing another destroyed the sentence meaning.