The best advice is to watch your clock, know that at 10:00 I should be through x number of problems so that at 10:00 you know where you stand, I can't telll you how many gasps I heard when they announced 15 minutes. The other little tid-bit is to keep track of the amount of questions you know for certain are correct. When I left I was certian I had over 70% of the test correct so the guessing or ones that I was fairly sure about would only help that amount and that really helps with peace of mind, because if you think the stress is getting high now just wait until the first states start to report, you will go nuts waiting.