1. First find the "Prt Scrn" (short for 'print screen') button on your keyboard.
2. Then when you are on the screen you want to take the screen shot of, hit that button.
3. Now you will need to open up a graphic program. Any one will do. Windows Paint will work, or any other similar program.
4. Now you want to find the option to "Paste as New Image" (or similar wording) within that program. This should create a new image with screenshot.
5. Then save the image and you should be good.