Swipe down to access the quick settings from the top right corner of any screen, and then click the “Screen recorder” icon 
to create your recording (click “Edit” icon 
, hold and drag the "Screen recorder" tile above , then tap "Edit" button to add the tile)-> select “Share one app” or “Share entire screen” that you want to start recording or casting with Screen Recorder-> touch “Next” (or “Start”). Select “A single app” will let you only screen-record or screen-share a specific app rather than your entire screen.
For additional set up options, go to the main menu -> “Settings” ->“Advanced features”->“Screen Recorder”.
Note: Available settings and menus may vary depending on device model and software version.
