It is no joke and alot of information to digest. As far as uniform goes, you have to have it on and they do daily inspection for those who have them. Many people did not have theirs yet, so do not be concerned about that. I think a few people got them because the instructors actually made some phone calls to push people along. It is alot to digest, but do not get overwhelmed. Know your 5's and 10's, that is the main thing. I passed my 10's yesterday, but failed my 5's by missing "Safe path on turns" and I said "Safe path and turns". Retaking it today. Once you realize it all fits together the 5's and 10's, it will click". I have been working preload for almost a year and have been running AM air for almost a month, so I have plenty of DIAD experience which is helpful. If you are in a center, see if you can go out with a driver one day to learn it. It will help you in class and while testing. Overall a good experience, but again, a ton of information. I have my own business and ship about 200 packages each week for the last 14 years and have used everyone, UPS, Fedex, and USPS. You will realize why UPS is a held to a higher standard. You will do fine. Just get the 5's and 10's down. I have no interest in becoming a full time driver, just seasonal, and Air as I only want part time, but work hard and learn it because its a good paying gig. For those 4-5 days, shut everyone and everything out of your life if possible. It will pay off in the long run.