Size a window using the keyboard

Step 1. If the window is enlarged to its maximum size:
Restore it to its original size by pressing ALT + spacebar to open the application Control menu, and then select Restore.

Step 2. From the application Control menu, select Size.

Step 3. When the mouse pointer changes to a four-headed arrow, use an arrow key to select the border you want to move. For example, press the UP ARROW key to select the top border.

Step 4. When the mouse pointer changes to a double-headed arrow, press the arrow keys until you move the borders as much as you want.
If you need to return the window to its original size, press ESC.

Step 5. When you finish changing the size of the window, press ENTER.

Note: You can change only one window border at a time. Repeat this procedure for each border you want to change.