Mouse shortcuts

SHIFT CLICK in between guides

 * Create 2 guides on screen (drag mouse verticaly or horizontaly from ruler area toward where you want the guide to be)
 * Select one a creating tool, like "new text frame" or "new image frame" (using the buttons)
 * SHIFT CLICK inside the space (hold on Shift + left-click)

See : the created frame occupies all the sapece between the guides and the margins (which are also guides)