Global Category Pages

Hi there

Is there a way of editing the layout of a Global category page? I am happy to pay a developer to sort this but want to make sure it is possible and also how difficult this is? At the moment it is all in one long list and I have no side-bars. I would like to retain the side-bars which I have on all the other pages and have the products in a grid like layout rather than a list. This is on a Global category page layout.

Kindest regards