The trouble with the application is that you still have to miss with moving tables around to fit on one page. some ai would be nice… (CA ERWIN HAS THE SAME PROBLEM)
you can display print area in workspace. Click Settings | Options and in section Graphics select the Visible Page Boundaries checkbox. This will display lines in your ER Diagram. If you wish to resize diagram to one page, there is a workaround. Export diagram to picture and then print the picture.