Measures per line

How do I specify the number of measures per page line in a score? If I just want 4 measures to appear fully across on the page width, for example, is there a way to set up the score that way? And if I want to add 4 measures to a score and have them drop down below my existing measures and appear on a new, separate line across the full page width, how do I do that? I get how to add measures but not how to do it in this way. (I've checked the handbook but somehow can't find the answer though I know it is probably there somewhere.)