Adjust the perspective grid and the active plane widget

Select View > Perspective Grid.

From the Perspective Grid submenu, select the following options, as needed:

• Show Grid or Hide Grid: Toggles the visibility of the perspective grid on the artboard.
• Show Rulers or Hide Rulers: Toggles visibility of perspective rulers aligned with the grid planes.
• Snap to Grid: Allows snapping to gridlines while moving, scaling, and drawing objects in perspective or bringing them to perspective.
• Lock Grid or Unlock Grid: Prevents or allows moving and editing of the perspective grid.
• Lock Station Point: Locks the position of the station point to avoid unintended perspective shifts. You can move one vanishing point in sync with the other vanishing point.
• Define Grid: Opens the Define Perspective Grid dialog box to customize grid size, angles, color, and layout.
• One Point Perspective: Changes the grid to a one-point perspective, with a single vanishing point on the horizon line.
• Two Point Perspective: Changes the grid to the default two-point perspective, with two vanishing points on the horizon line for angular views.
• Three Point Perspective: Changes the grid to a three-point perspective, adding a third vanishing point above or below the horizon line for vertical views.
• Save Grid as Preset: Saves the current grid settings as a reusable preset for future projects.

Double-click the Perspective Grid  tool.

In the Perspective Grid Options dialog box, adjust the following options as needed:

• Show Active Plane Widget: Controls the visibility of the active plane widget.
• Widget Position: Specifies the position of the active plane widget in the document window.
• Automatic Plane Positioning: Uses Anchor Point of Perspective Artwork and Intersection of Gridlines to create objects by inferring the height or depth of the object.