To edit the size of your call sheet page, go into editing mode on the call sheet you wish to change.   Once in the call sheet editor, go to the "Page Settings" tab:

Then scroll down until you see the page size options:

Here you can customize the page length or width as needed.  
If you are having issues with content running off the bottom of the page, we recommend increasing the page height until all the content fits on the page as needed.