For more details see the Extended Order Grid extension page.
Add more functionality and flexibility to Magento order grid. The Extended Order Grid extension provides you with the ability to add extra columns, utilize the advanced filtering, and save grid templates to switch the order grid view in a few clicks.
To configure the extension, please, go to System → Configuration → Extended Order Grid.
Max products display per order on the grid — limit the number of products to display on the grid from orders;
Hide Configurable Parents — choose Yes to hide configurable parent product's attributes from the order grid;
Hide orders with statuses — hide orders from the grid with the defined statuses.
To add new columns to the order grid, please, go to System → Amasty Extended Order Grid.
Then, tick the fields you want to add to the order grid. In the Order column, you can adjust their position on the grid.
Use the Width column to adjust the field's size on the grid.
When done, please, hit the Save Columns button.