How can I make my screen easier to read?

Frank is frustrated because his Windows 10 screen is unreadable. It's frustrating because the white background and the blue letters make it difficult to read. Leo says that in the Accessibility settings of Windows 10 there is a high contrast mode which he can turn on and off by holding down the left "Shift," "Alt," and "Print Screen" keys. He can also choose to turn it on permanently in the settings.

Image: Cryptic C62; article: Wikipedia authors, see history of w:Boldering (screenshot) [CC BY-SA 3.0, GFDL or CC BY-SA 3.0], via Wikimedia Commons

Check out the original question from June 11, 2017 here.