Deleting cookies in Firefox is pretty easy. Start by opening your Firefox browser. You will click a series of tabs to delete all or part of the cookies on your computer. Click the 'Tools' tab and go to 'Options'. In the 'Options' box choose 'Privacy'. Look for the 'Cookies' section of the box and choose 'Show Cookies'. That will bring up a list of all the cookies on your computer. Choose 'Remove Cookies' or 'Remove All Cookies'. Then close everything and restart Firefox and you are all finished.