Apple iWork '08 - Manual (Page 50)

50 Chapter 1 Getting Started with Pages
3 When the window displays the portion of the image you want to appear, double-click
the window, press Return, or click the Edit Mask button.
The borders of a masked image are dotted lines. You can drag a masked image to
reposition it on the page, and you can drag the selection handles to resize the image.
To change the size of a mask:
1 Double-click the masked image.
2 Click the dotted border of the resizable window to select it (the hand pointer turns to
an arrow pointer when it is on the dotted border).
3 Drag the window, the selection handles, and the slider to remask the image.
4 When the window displays the portion of the image you want to appear, do one of the
following to exit masking mode:
 Double-click the mask window.
 Press Return.
Drag the slider to zoom in
on or out of the image.
Drag the photo to position
it in the mask window.
Drag the selection handles
to resize the mask window.