Tracking Inventory with Options

I am having trouble with understanding how to track my clothing inventory on my cart. I have a shirt added to the site and changed the option to track inventory with options and figured when I go into the options menu that has my different shirt sizes options that I would be able to add in inventory for each amount of sizes that I have but I am not. When I click on the edit link next to the inventory it takes me a combination’s page that seems like it is not setup. What step am I missing? I feel that just adding another field in the options menu for inventory number would be super efficient enough. Seems like the current method may be confusing to setup?

Any help would be great. Thanks for the great software!

Nevermind I was able to figure it out. I had to check the inventory check box in the options menu.