You should think about the keywords people will search for this topic and include these in your title and in your post – so that they find your blog. Then to tag your post, add meaningful “categories” or keywords – but no more than one or two. All of this will add to your SEO (search engine optimisation).
This actually helps to discipline you to focus a blog post – maybe if you need more than three or four categories to describe it then what you need to do is divide this complex topic into more than one post?
TIP: divide a long post into many smaller posts
For example, this series of posts about how to write for your blog originated as a behemoth of a post on another blog. By separating the long post into many smaller posts on this blog we hope to make the message easier to read.
And what about Tags? …for another blog post – watch this place!