Even if you feel like you don't need your break in the middle of the test ...use it. It's nice to stretch your legs and walk around. Also, YMMV but I think it's important to use all the time allotted in each section, even if you finish early.
DON'T use the extra time to go second guess yourself, just use it (if you even have extra time) to make sure you didn't make any dumb mistakes or left any blank. (I caught myself twice on this trying to speed through..or I had thought I clicked it but I did not.)
Also, if you are cutting it to the wire, start guessing...it can't hurt you.
Good luck.
DON'T use the extra time to go second guess yourself, just use it (if you even have extra time) to make sure you didn't make any dumb mistakes or left any blank. (I caught myself twice on this trying to speed through..or I had thought I clicked it but I did not.)
Also, if you are cutting it to the wire, start guessing...it can't hurt you.
Good luck.