Imposing automates the production artwork file creation task; else your graphics designer has to do it manually. It reduces the manual intervention in print production as well as reduced chances of error.
You can manage several sheet options in different dimensions (height and width).
Assign a default sheet to a print product, so that when an order comes, the print-ready artwork file can be prepared based on the given sheet size.
Define the bleed margin as required for printing.
A print ready PDF will be generated with artwork imposition, and you can review it and process for printing.