Press Alt+Tab to move the highlight to the window you want to resize.
Press Alt+Spacebar to display the Window menu.
Press S, the menu's mnemonic for Size.
Press the arrow keys to stretch or shrink the window. An outline appears to show you the window's size.
Hold down Control while you press an arrow key to size the window faster.
When the outline shows the size you want, press Return.
To cancel the resize operation, press Esc.