From the LSAT last month:
19) If there are rules about what you can and cannot bring into the test, follow them.
20) No, really, the rules won't be bent for you.
21) Administrators, familiarize yourself with the rules. If there's a rule that states "No digital watches," learn AHEAD OF TIME what a digital watch looks like. This is really basic, common knowledge and your lack thereof shouldn't slow down the test.
22) If you have a tic or a special need, see *ahead of time* if you can get accommodations for it.
23) If they say leaving the test center before the test is over will invalidate your score, that doesn't mean there are exceptions for you and your panic attack, hunger, important phone call (oh, remember that rule about no cellphones?), etc.
24) Administrators, jokes and stories before the test are fine, but maybe you could keep the really scary ones to a minimum? Five minutes before the test is an awful time to get psyched out.