1. Category. What do you want to call the category that things will be organized under in the product section i.e. Commercial Flooring
2. Then they created 2 sub /child categories: carpet and resilient
3. Manufacturer. Every page you create needs to be assigned to both a manufacturer and a category in order for it to appear. In the case of Graphic they wanted all their manufacturer pages to be listed together under a sub category. So they fooled the system and put in a bogus manufacturer called Carpet.
4. Pages. Then they built one page for each manufacturer and assigned each page to the same manufacturer: Carpet and assigned the pages to the same categories : Carpet, and Commercial Flooring.