You can resize the entire icon or a region of the icon.
Choose Resize Icon from the Edit menu.
Icon Editor displays a dialog box that prompts for the new size.
Edit the current width and height to specify the new size.
If you make the icon smaller, the right and bottom edges are clipped off. If you make the icon larger, the existing image remains in the upper left of the icon.
Select the area of the icon you want to resize using the Selection tool.
Choose Scale from the Edit menu.
Drag a box that defines the size and shape that you want the scaled image to be.
The size of the box is shown in the upper right area. This determines how the selected portion of the image will be scaled; it does not determine where to place the results.
Position the outline where you want to paste the scaled copy, and then click.