Ensuring that editing is turned on, choose the topic to which you want to add your glossary, click on Add an activity... and select Glossary from the list.

You need to give your glossary a name and describe its purpose. Mine is a glossary of ballistics-related terms to help you as you work through the course. In the description, I'm also going to mention that anyone can add to this glossary.

Because students are adding entries to this glossary, I'm going to allow all entries to be rated. I'm going to allow everyone to rate entries (I need to be vigilant and ensure that there is no favoritism or special deals going on), with a maximum "grade" being a mark out of 5.

We can leave the rest of the glossary configuration settings set to the default, but if you want to have a play around with them then remember that you won't break anything. When you are happy with the settings, press the Save and display button. Your new glossary is now ready to have entries...