- Find the button on your keyboard that says: PrtSc (Print Screen).
- Set up whatever you want on your screen to be taken. Press the button.
- In the Start Menu, go to Accessories, then launch the Paint program.
- Paste the image into the blank Paint file, crop it until you have what you want left (remove useless parts of the screen that was taken), and save it as a PNG file (for better quality).
If you have Microsoft Office Word, you should have it opened when you are doing this because you can open the clipboard (thing that keeps everything you've copied), and clear it after each screenshot.