The ‘Print‘ button on the top menu bar takes you to a print window where you can create A4 to A0 files to print. As well as page size there are a number of options allowing you to set the title, print scale, print format, page layout, as well as include additions of national grid lines, annotations, hill shading and legend. The ‘Content Preview‘ tab shows a small area of map content, the ‘Layout Preview‘ ab shows the extents of the area that your map will cover. The map can be dragged in either preview tab to change the extents covered
See also help page – Point 7. – http://digimap.edina.ac.uk/webhelp/os/osdigimaphelp.htm#getting_started/i_just_want_a_map.htm