To create a new product and sub product line .. this is what you do ….

1 : go to your my zazzle
2: click on products tab
3: at the top of the page you will see it says
Create new product | Add new category | View in store | Hide all | Unhide all | Alphabetize
click add new category .. give it a name ..
4: to create sub categories .. click on your created categories on the left and add a sub category to them ..

to add all ready created products to your new categories .. go to your public products .. either move an individual item by clicking edit above the thumbnail or tick the box under a selection you want to move in to the same category and at the top of the page under the “all products” title you will see it has “move to” highlighted .. click that and move the items to their new category