As you already know, blog posts should be assigned to categories, typically only one category per post (although you might see a reason for using more than one category in some cases). The categories are for the readers’ benefit in two ways: they can easily tell what is the general topic of a post by looking at its category, and they can sort content on your blog by clicking on a particular category link.
Your study guide blog most likely came with a category for research notes, but that category is for your benefit, not your target audience’s. So you’ll need to give some thought to which categories would be most appropriate to your audience, given the kind of material you’ll be posting to the study guide blog and how readers will want to sort through it. Also consider which categories are likely to be most helpful to your primary and secondary audiences (as described on the Audience and Purpose page
For example, you might create categories for each of the discourses you’ll be finding examples from. Or you might create categories for sub-topics within your larger topic. You’re unlikely to hit on the perfect set of categories right away, so be open to letting the categories evolve with the site (but keep in mind that changing the categories may mean editing earlier entries).
To add or edit categories, go to the study guide dashboard, click on the Posts tab, and then click on the Categories link. You’ll see a box you can use to create new categories. To edit an existing category, just click on its name.