First find the Print Screen (Prt Sc) key on yer keyboard. It may share a key, so to use you might need to hit Shift at the same time.

So:

Have yer Team on screen, hit "Shift+Print Screen" this puts the image on screen to the Clipboard.
Open an image editor, like Paint.
Hit "Control+V" or use the mouse to select Paste.
Crop out what you don't want.
Save.
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