Call me stupid, but how do you change the size of a form with code, (not using the visual interface)

Code:
        'this is part of the print preview section
        'don't want to maximize or have centered
        '     I am using dual monitors in horizontal mode
        '     center spans both screens, maximize fills both screens
        '     want to be able to size the form to fill only one monitor
        dlgPreview.WindowState = FormWindowState.Normal
        dlgPreview.StartPosition = FormStartPosition.Manual
        'I want to size the form myself here
Thanks, Chris