E-commerce bloggers must carefully write keeping their audience in mind. Everything you post on your blog will speak for your product or service. Your interaction with bloggers in comments and otherwise will give you a direction.
Series of articles - Create a series of articles on your blog if the subject you choose to talk about is an extensive one.
Tags: Use of relevant tags is important from the SEO perspective. It helps the search engine track your post based on the tags you use.