Use guides

When rulers show (View > Rulers), you can drag horizontal and vertical guides from the rulers onto the Stage.

When you create nested timelines, draggable guides appear on the Stage only when the Timeline in which they were created is active.

To create custom guides or irregular guides, use guide layers.

• To display or hide the drawing guides, select View > Guides > Show Guides.

  Note: If the grid is visible and Snap to Grid is turned on when you create guides, guides snap to the grid.
• To turn snapping to guides on or off, select View > Snapping > Snap to Guides.

  Note: Snapping to guides takes precedence over snapping to the grid in places where guides fall between grid lines.

• To move a guide, click anywhere on the ruler with the Selection tool and drag the guide to the desired place on the Stage.

• To remove a guide, use the Selection tool with guides unlocked to drag the guide to the horizontal or vertical ruler.

• To lock guides, select View > Guides > Lock Guides or use the Lock Guides option in the Edit Guides (View > Guides > Edit Guides) dialog box.

• To clear guides, select View > Guides > Clear Guides. If you are in document-editing mode, all guides in the document are cleared. If you are in symbol-editing mode, only guides used in symbols are cleared.