Open your browser and log into your account at https://app.mangodisplay.com
Open your preferred display.
At the top right corner of the main screen click the Settings icon ⚙️
Then click 'Display Orientation' on the settings window.
Choose 'Rotate 90 degrees clockwise' on the dropdown menu.
Click save and you're done! It will automatically show on your display.
You can also enable the 'Set Layout Designer to match Display Dimensions' option, to make your layout designer match your display orientation and aspect ratio. This option will ensure that the orientation, size and aspect ratio of your layout designer matches your display.