Brand new Custom Store- how to write product categories for SEO

Hello! I am brand new to this with a custom store from Alidropship. I just finished writing product descriptions for the products that were loaded by the store creators (that took me forever!). Now, I am writing the product categories for SEO, but I am not quite understanding what to do. Below is a screenshot from the article, "The Art Of Product Page SEO: Optimization That Generates $10,000 Per Month In Our eCommerce Stores" written by Olga. I am trying to follow these instructions, but it's not clear to me how it all works. Could someone give me an example of how they wrote theirs? Do I not make the product categories specific to that actual category, or do I make it about the general products sold in the store (which is what it looks like on the screenshot from the article. Thanks for any help! Screen Shot 2018-12-19 at 9.41.12 AM.png