If you have a standard keyboard find the row of "F" keys. They should go "F1" "F2" and so on until it gets to "F12"
To the right of "F12" there should be a key that says:
Hold shift and press that key at the same time. Then go into paint, click on the canvas and hold ctrl+v.
And magically it should appear. then just save it as a jpeg and you're good to go.