The Mario Kart Racing Wiki is organized into various categories to help users easily find pages that they could be looking for. However, not all categories are acceptable on pages. This page breaks down how to categorize.
Let's say you are creating a page for a track. Obviously, you need to add the category Tracks. You can do that by typing "tracks" on the category module at the right side of the editor. While you are doing this, you also need to know what games you are creating the track page for. If it is a track in Mario Kart 7 that reappears in Mario Kart 8, you need to add "Mario Kart 7 tracks" and "Mario Kart 8 tracks" as categories. Make sure that "tracks" starts with a lowercase t. You also need to add categories based on cups. So you would add "Example Cup tracks" as categories.
What about racer articles? That will be answered as well. Racer articles follow the same principle. Add the category Racers and Mario Kart 7 racers, or whatever games they appear in. This works for almost everything on the wiki! Just make sure you are using the right base category. These are acceptable: