Hey... ...that's confidence!
I am sure you will be fine, the exam feels harder than it is to pass IMHO.
I prepared by having a game plan, I mean if you are designing and coding as part of your job, you should be getting all the practice you need, right (except for the fact you don't have access to your tools, templates and reuse code etc...)?
I had a chat to Omar before taking the exam and he summed it up best for me: Quite simply, start at a high level and get the framework down, then iterate over it as many times as you can adding detail (code or requirements) keeping in mind you don't have to code it - that's not the point of the exam. So I pretty much followed this top-down approach and it works well.
Cheers
-JG