To set the media size:

1. Choose Document > Advanced Processing > Imposition or click the Imposition icon on the Tasks toolbar.
2. Click the Media Tab.
3. Check Autosize Media to print the imposition file to a medium which is fit to the size of the page content. And you can also check Fit to media size to print the imposition file according to the size of a specified medium. If you have selected Fit to media size, do any of following to specify the size of media:
   
   • Select a medium from the list, there are several default media (Letter、Legal、Executive、Ledger、Tabloid、Screen、A3 and A4) and other custom media. Only custom media can be edited or removed.
   • Click Add to add a custom medium. In the Custom Media dialog box, you have to name the medium as well as define its width and height. Click OK to add this custom medium to Media list. Valid width and height values are from 0 to 100 inches.
4. Select Auto Rotate to rotate the imposition file pages when the medium width-height proportion is not fit to imposition file pages.

To place the page content on a medium:

1. In the Media tab, check Fit to media size, and then specify a medium.
2. In the Margin group, set set margins (left, right, top and bottom) for the medium (unit page edge to medium sheet edge) when print. A valid margin value is between 0 and 100 inches.
3. Set horizontal and vertical scalings for the page content. The valid input number is integer from 1 to 9999.
4. Click Options tab, and select Scale Larger Pages to ensure all pages of the original PDF have the same size on a medium sheet. If the original PDF pages are in different sizes, all of them will be adjusted to fit to the first page when print.

Media Settings