You can move and position layout frames in the Layout window by snapping them to a background grid or guideline. Snapping is an effect where you move a layout frame near a guideline or a grid line and it aligns and attaches (snaps) to the line. This is useful for arranging multiple frames so that their edges line up perfectly.
Grids and guidelines are commands that help you design a layout. They do not display in printouts or exported images.
When working with the grid and guidelines, you may want to zoom into or out of the view in the Layout window. For instructions on how to do this, see Re-Center and Specify a Zoom Level for the Layout Window.