If I need to make a new shipping rule I should go to Extensions from the main menu, extensions, select Shipping then select the X-Shipping Pro plugin on the pencil button to open the X- Shipping Pro.
On the left in the Global Setting column I can create a new rule or edit an existing one.
After selecting or creating a rule, when I select it on the right, its settings page will open. I can add a name, description, and in the Product Rules tab, create related rules from the product options. In this particular example, I have defined the size or I can make a rule to get a different price depending on the category of the product.