By tabbing the CERM, I'd definitely tab within chapters, possibly things like sub-sections/sub-topics, design processes, important equations, etc. Whatever sticks out to you when you're doing practice problems. Label with simple notes that will immediately let you know what the tab is referring to.
Really, you can organize your materials however you like, in whatever way makes the most sense to you. This includes tabbing, but as for breaking up your materials between the morning and afternoon sections -- this could be advantageous because it's very likely that you won't need any of the practice problems that were applicable to breadth topics outside of your depth subject (like hydraulics or structural stuff, etc.) for your depth section.
It can also be easier to manage smaller binders, vs. one huge binder with ALL of your practice problems.
As for the contents of these binders? Surely, there are worked out practice problems in them. Other things people might include things like cheat sheets with common equations and design procedures, other resources printed from pdf (like useful tables or other design references), anything that you think might truly help in the exam.
However, I do caution against bringing along things you are not familiar with, because if you find yourself searching through a bunch of stuff you're not familiar with, you might also be wasting very valuable time that could be devoted to other problems that you're more likely to get right.
