Background - Structural engineer with 12+ years of experience. I first took my structural 1 in 2010 and passed first try. I only took the SE exam this past April and passed both of them. I must admit that my experience probably helped me through the afternoon problems on both days.
I agree with many that the test is pretty difficult and you have to be on your A game for 16 brutal hours. However, I do not think that the questions on the test were as ridiculous as people above are claiming it to be. I think they were fair to the most part. There were certainly many curve balls and problems intended to lure you into the wrong answer. However, as a practicing engineer, you should be trained to pick those up. The test is designed to drill down into the nitty-gritty in the codes. Unfortunately for many of us, we only utilize 30-40% of the code to design 80-85% of our day-to-day problems. However, the test is designed to check your knowledge on 100% of the code, meaning any question from a code is fair game. There is no way other than going through the codes in its entirety and not skip on topics thinking you will get lucky. I believe most of all the problems were code-related and didn't require knowing some obscure material. If you spent time trying to invent a method to solve the problem, you are already on the wrong path. You need to have a very good understanding of statics, load paths, design principles to pass this test. This test cannot be passed by going through the SERM one time, period! You need to review multiple resources, especially on topics you don't design/detail on a daily basis.
I would suggest spending a lot of time sharpening your analysis skills (I used the problems on www.mathalino.com as a resource). Create cheat sheets, write down formulas as you work out problems every time so that the formulas just end up getting memorized. Don't tab your books until 2 weeks before the exam. The goal is to know the material by flipping to it every time so that you know exactly where to find it without relying too much on tabs.
Many of us work in firms where you are not exposed to all different types of materials, structural systems etc. It is up to each one of us to plug the gaps. In my case, I had a lot of brushing up to do on wood design because I personally don't care much for wood. I had to re-learn the concrete code because I took the test in 2010, I did it with ACI 318-05 and to date know where to find things in that code. ACI 318-14 was a difficult adjustment. AASHTO was a bear as well. Do not skip studying AASHTO if you are a building engineer. It's likely that a straight-forward code lookup from AASHTO might cover you for a curve ball from ACI/AISC/ASCE etc. The David Connor book was a blessing to help go through the code sections in AASHTO. My strategy was to work out all the building problems first and then do the bridge problems last. Put the AASHTO index on the front of the code to make looking up easier.
It is critical to know how to analyze problems without the use of a computer, which we use indiscriminately at work. There are many analysis aids, force/moment/deflection formulas available as resources and you should familiarize yourselves with it. I cannot stress the importance of knowing how to shortcut into an answer by using these design aids. Time is always going to be an issue.
Work out as many problems as possible in its entirety, don't skip steps or look at the solutions, no matter whether it takes you 20 minutes to solve it the first time. Your knowledge of flipping through the codes and reference material to solve the problem is invaluable. Practice, practice, practice - that's the only thing that will help you cut down on the time to solve a problem. The only way to know what you are tripping up is to work the problems out and cement your understanding of how to approach it.