First of all find an interesting thing you
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what to print. Then (if you are using Windows) find a key that says Print screen, (look right and then go to the top it is normally there)[spanish ImpPnt:Imprimir Pantalla] then press it. Next, go to paint, or any equivalent program, an click paste. Finally you can edit it as you please (paint, erase, modify, change size, convert into image, print...).
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Find an interesting thing to print. Then (If you are using Mac) press command + shift + 3. Next, make a screenshot.
Finally yoy can edit it as you please (paint, erase, modify, change size, convert into image, print...).