QUICKLY!

Easy!

你 hit the "Print Screen" button on the 最佳, 返回页首 right side of your keyboard.
It's to the left of "Scroll Lock" and "Pause Break"

That is basically like right-click=copying your whole screen, so 你 have to paste your screencap somewhere and save it.

MS Paint works really good for that. Then 你 can do what 你 like with it, like save it, 编辑 it, etc. 或者 save it and 上传 it to some other program.

Hope this helps!

Either use prntscrn button on your computer, the snipping tool if 你 have Windows 或者 use VLC player to screencap a video (there's a really good tutorial on this somewhere in livejournal).