The Get Safe Online website gives good and safe blogging advice. Here are some examples:
If you are new to blogging, start cautiously. Understand the features of the software you use and how the blogging community (the ‘blogosphere’) works, including how to filter comments.
If you want your blog to be public, disclose only what you want everyone on the Internet to know. Otherwise, keep your blog private.
Keep details that identify you only to yourself and trusted people.
Remember – what you post online stays online ... anything you post remains in the public domain and accessible indefinitely. Even if you subsequently delete the post, it may have been cached in a search engine or internet archive, or in a company server.
You may think you have a small audience, but blogs are public and it is very easy for people to find information on them via search engines.