When you shift a text or graphic object the position assistant will take action. Centered or aligned? Leftor right? Above/below? You decide, and the assistant helps to place the object correctly. The object "snaps" at the ledger line (can be deactivated).
Align heading to centerline - very easy:
Align objects horizontally - ledger lines over the entire width:
Align objects vertically - exactly one above each other: