You attempt to register for Step 1 or Step 2. If it kicks you out before allowing you to register, you have supposedly passed the Step.
However, I tried the "trick" for both Steps 1 and 2 and the system allowed me to register. After experiencing much anguish over failing Step 1, I found that I had actually passed. I tried this again for Step 2 (sans anguish) and learned later that I had passed. So the trick does not work. It just f*cks up your USMLE transcript.
Save yourself the anguish and check with your office of Student Affairs once you see that your score is posted.