The blog can be used for whatever you want so long as it falls with the site rules. We encourage you to post about writing, but you can also post your work for display (rather than critique in the workshop), or post about your personal life or generally anything you'd like within reason.
It should be noted that the blogs are not the debate room so while you are allowed to blog about contentious subjects such as politics, religion, equality, political correctness, etc, we will not allow a prolonged debate to develop in the comments.
Also you may not use your blog to post Erotica. Our Erotica sections here on the forum are closed to members under 18, for legal reasons. Access to our blogs is not age-restricted, so if you want to discuss Erotica or post any samples of Erotica writing, please post in one of the two Erotica subforums.
Posting to your blog is easy. First navigate to the blog section. This is the tab labeled "Blogs" in the menu on the forum start page:
Once there, in the top right there is a button labeled "Create Entry":
And that's it! Now you can fill in your blog entry title, text, entry date, category (you can create new ones) and set your privacy settings. Then click the "Create" button on the bottom.
You've just posted a blog.