I did the FIC test about 2 months ago.
It used to be that you did your initial test and then you could avoid having to be tested again by revalidating each 3 years with both experience and seminars. This made the initial test quite rigorous because it was the only time to check your standard of instructing.
Now you have do another flight test on your first renewal. Apparently this has made the initial flight test a tad more relaxed.
This is what my examiner explained to me anyway.
I think if you prepare for the test like any other then you will be fine.
Good luck.