How do I add old/new listings into sub-categories?

Add new listings to sub-categories

To add new listings to sub-categories, simply click on Sell > Category > Choose parent category (e.g. Games & Toys) > Choose sub-category (e.g. Toys). 

Add old listings to sub-categories

The process is similar. Simply click into your listing > Edit listing > Category > Choose Parent category (e.g. Design & Craft) > Choose Sub-category (e.g. Craft Supples & Tools) > Save