At the login page, in the top right corner it will show the default keyboard layout "us". If you click this, a new menu will appear listing all the available keyboard options. Simply select the option that best applies to your keyboard.
One you have logged in, the current keyboard layout will be displayed in the bottom right corner of the screen. By default, you can swap between US, GB and DE layouts by left-clicking on the current layout or by pressing both SHIFT keys at the same time. To add or change the available keyboard layouts, right click on the current layout and select Keyboard layout handler settings.