I took the september LSAT yesterday. When you finish the 2nd section you just bring your ID to the desk outside the test room and tell them your on break. Mine had a clock outside but just make sure to keep track of your timing so you don't come back late because it will automatically start. When you come back they will scan you again and then lead you to your desk again. Once you press ready on the screen, you will check a few boxes that you did in the beginning to verify that you didnt use your phone etc. and then the next section pops up and you click start!