The Collection page features a simple toolbar on the left where you'll find a search form, filters and sorting options.
To filter your line sheet by Line, Category, Color and so on, simply choose one or more of the drop down filters in the left hand menu.
There are also three ways to sort your products in the Order By drop down:
Your line sheet product order is set to 'Relevance' by default. This preserves the order in your original spreadsheet.
Order Alphabetically across all your products.
Break down the line sheet by category. The products within each one will be ordered alphabetically.
By default the Categories are sorted alphabetically, but you can customise their order. To do so, go to the Products section, click on the Collections link in the toolbar, then select the Collection you want to edit.
Inside the Collection, you will find the list of the related product categories, and you can drag and drop them to change the order.