Where do I find the reset for the clone stamping tool? I saw a screen shot for an answer below, but I can't locate it.

Honestly, I'm not sure. I'm taking an online graphics design class and my clone stamping tool wouldn't work.  I saw the Q&A below so I thought I'd try to do that.  When I click the clone stamping tool now, a big circle shows up and it still doesn't work.  I'm not really sure how I'm going to get through this class unless I have a tutor-that's how I learn, by someone showing me where to go when I get stuck.  Any suggestions?

Thank you, I did find it this time.