Drawing Artboards
Here's another approach to generating multiple artboards for a new document. This setup allows more flexibility in defining multiple-sized pages.
Every document has at least one artboard. To create additional artboards, from inside or outside that original artboard, draw one or more rectangles and choose Object > Convert to Artboards (see Figure 2).

Figure 2 Converting selected rectangles—on and off the initial default artboard—into separate artboards.
You can use this technique to create artboards from within the regular Illustrator document window, without disrupting the flow of your design work. You can create up to 100 artboards this way.
Creating Artboards from an Existing Document, or Editing Existing Artboards
If you're working with an existing document (one artboard), or you want to edit the number, size, or location of existing multiple artboards, click the Document Setup button in the Control Panel (see Figure 3).

Figure 3 The Document Setup button in the document Control Panel.
Clicking the Document Setup button opens the Document Setup dialog. Click the Edit Artboards button (or press Shift-O) to start Edit Artboards mode. In this mode, you can drag the corner handles to resize existing artboards (see Figure 4).

Figure 4 Resizing an existing artboard.
Alternatively, you can click an area of the document (inside or outside any existing artboard) and draw a new artboard (see Figure 5).

Figure 5 Drawing a new artboard.
A modest Control Panel in Edit Artboards mode allows you to control the properties of a selected artboard. You can use the Control Panel tools to do the following (see Figure 6):
- Use the Presets pop-up to choose preset sizes for a selected artboard.
- Toggle between portrait and landscape orientation.
- Generate a new artboard with the same properties as the selected artboard.
- Delete an artboard.
- Move or copy artwork within an artboard when you move the artboard. (By default, moving an artboard does not move artwork within that page.)
- Define center mark display.
- Access artboard options in a dialog.
- Define dimensions of the artboard by entering values in boxes.

Figure 6 Control Panel tools in Edit Artboards mode.
To exit Edit Artboards mode, click a tool in the toolbox or press the Esc key on your keyboard.