definitely take a thermus of strong coffee with u and take a few gulps every break u get. i get very drowsy too around 1-2pm but for some reason all the stress and adrenaline from taking the test kept me wired.
I personally would avoid caffeine as it obviously is a diuretic and may cost you some precious break time if you know what I mean. The exam day diet that has worked best for me is a bagel w/ cream cheese and a bottled smoothie. Preface that w/ a good night of sleep and a solid breakfast and you are good to go.
100% agree on both points. Watch out for the caffeine. I overdosed on coffee for Step 1 and I flew through about the last 20 questions on one of my later blocks due to an acute need to micturate. 😱