In the Links Module checking Sort Main Only hides all item settings and info except for the link category name making it easier to sort the link categories. The sub category sorting is within that category only.

The Item Info Section contains the item's info and an Edit link that takes you to the item editor. You create a new category using the Add Category & Link link above the Page Header Editor . Add sub categories using the add link link above the sub category links.

Links Module with sort only checked and auto sort unchecked: