There are a number of free/open source screen readers available for Windows users. One of the more popular ones is NonVisual Desktop Access (NVDA). Take a bit of time beforehand to download the software and learn some of NVDA’s documented basic keystrokes. Mac users, you have a built-in screen reader called VoiceOver on your systems. Take some time to visit the site referenced to familiarize yourself with how to turn on VoiceOver and some of the basic keystrokes. On May 18, unplug your mouse (blind users do not use the mouse), launch your screen reader, and spend an hour using some of your favorite sites strictly using the keyboard alone (tab/shift tab, arrow keys, enter and spacebar) and not the mouse/trackpad. Why not turn off your screen and depend strictly on the information conveyed by the screen reader.