First of all you press Prnt Scrn or Print Screen next to F12.

Then open paint and paste

Save the file as a JPG (J-PEG)

go to http://imageshack.us/

browse for your picture file

if you want to resize your image then press the drop down arrow where it says 320x240 then select the one you want

now press upload

after it has uploaded press direct link to see your pic.