You need to get to the testing center about a half hour before your scheduled time. The test probably won't start exactly at your assigned time (9:00?) because there is a whole check in process that starts when you arrive at the center and depending on how busy they are can take between 15-30 minutes. That's why you need to make sure you are there a half hour early. They check your two forms of ID, confirm that you are registered to take the test, take your picture, have you empty your pockets, and assign you a locker for your snacks and keys. You will lock everything but your IDs in the locker. Once you are ready to go into the test they will have you sign in on a paper with your name and all of your information and take your thumbprint. (Thumbprint and picture are just to confirm who it was that took the test, in case there is any question in the future). You will only be allowed to take your two ID cards and locker key into the testing area, don't try to take ANYTHING else, or you risk having your scores voided.
Once you are completely checked in, the proctor will walk you back to your desk, give you your two laminated sheets of paper, two markers, and a dry erase eraser. The test will already be up on your screen, and your name will appear as the person taking the test. Your 15 minute tutorial begins when you sit down at the desk. You can use this time however you would like, but when you push the "end" button for the tutorial, the 90 minutes for the Natural Sciences section begins, and the DAT has started. After Natural Sciences and PAT you have an optional 15 minute break. I would highly recommend at least using the bathroom and getting a drink during this time. They will have you sign out when you leave, and sign back in when you return. The second half of the test includes the Reading Comprehension and Quantitative Reasoning sections. When you finish those you will have a short survey about how happy you were with the testing center staff, conditions, computer functionality, test format, etc. You pick up all of your materials, return them to the proctor, sign out, and receive your scores! You're done.
Don't forget that the entire testing session will be videotaped by the security cameras in the cieling, so don't do anything that might be construed as suspicious, or you may not be getting into dental school for a few years, because your scores will be voided and you will not be allowed to retake for two years. Hope this give you a better idea of what to expect! Good luck.