How do I add and remove post categories?

1. From the dashboard, click on "Posts" in the left menu, then click on the "Add New" button.
2. Type in the title and content of your blog post.
3. Scroll down to the "Categories" section on the right side of the screen.
4. To add a new category, type in the name of the category and then click the "Add New Category" button.
5. To add an existing category, check the box next to the name of the category.
6. To remove a category, uncheck the box next to the name of the category.
7. When you're finished, click the "Publish" button to publish your blog post.

That's it! You now know how to add and remove categories while creating a new WordPress blog post.