Since everyone focuses so much on the content of the exam, let me provide a few pointers that will lead to a little less stress the day of:
- Bring cash with you (at least $20). You never know when something comes up that requires it. When I took the exam, the place it was held at was also hosting some stupid home & garden expo and was charging for parking (cash only).
Bring snacks. Quiet, non-messy things (like chewy granola bars - I recommend Clif bars). Take them out of the wrapper and pack them in Ziploc bags. Proctors will get mad if you're crumbling up wrappers or chewing potato chips.
Bring a drink. Water and/or juice is best. Make sure it is in a resealable container. An athletic waterbottle is better.
Pack your materials two days prior (not counting lunch, snacks, and drinks). Having to scramble to find everything the morning of the exam, or the evening before will no-doubt mean you leave something behind and then you're stressing over what is or could be missing.
Pack everything so that you can get it to your exam seat. It won't do you any good if you can't get it from the car to the exam room. Be sure to be able to carry it in one trip, multiple trips probably won't be allowed. Milk crates and banker's boxes work well, also look into portable luggage carts if you can't carry the box.
Bring a back-up calculator. Many simply purchased a duplicate and left it in the packaging. That way if you don't use it, you can return it.
Don't do anything exam related the day before. Take the day off as a "mental health" day. Go do something fun. I went out and test drove sports cars.
Drive to the exam site a couple days before hand during the same time period so you know what traffic patterns are like and so you can compensate accordingly. This is how I found out about the expo and pay-for-parking.
The weekend before, sit down and write something out for 4 straight hours. Get used to the feeling of sitting in one place and handwriting. You will not believe how much your hands will hurt if you don't at least practice handwriting for an extended period of time.
Night before the exam eat a good solid meal that won't cause you future problems (i.e. avoid spicy and fast foods). Pasta is a really good option.
Pack a lunch. Get something that will be filling, but not time-consuming to eat (like a sandwich). Do not expect the use of a microwave or toaster oven. Do not expect to have enough time to leave the testing center to go grab something from a restaurant or fast food place (see previous bullet)
Day of the exam, go through your normal morning routine. Eat your normal breakfast. Doing this will help with the nerves, trust me.
Show up early. There is always a rush of exam takers just before the cutoff time which leads to more stress for everyone. Get there before that wave.
Turn off the ringer to your cellphone before you leave the house. Not just the ringer, but also the vibrate mode. On the odd chance you forget your phone in your pocket, you don't want it ringing during the exam.
Going to the bathroom will NOT chew up too much time. If you have to go, then go. Your mind will work better if it's not focused on your bladder or bowels.
Hope this helps.