FL170, operators want to see that you can operate the aircraft safely, efficiently. So know your checks, inside out, back to front. And actually do them, don't just call them out. I have actually seen pilots call their checks out, when I ask if the checks are done they say yes, "oh, ok, so why aren't the landing lights on, how come you never checked the gear, fuel pumps still off" etc. Those guys don't get so far.
And if you get criticised, take it on the chin, don't sulk, don't pout, don't purse your lips and look away then argue. I've seen all of that, then they wonder why they don't get hired.
Also, know your rules, rights and obligations. Treat it just like a flight test. However, don't be intimidated by the pilot sitting next to you. Whether they be CP, Head of C&T, senior base or just a line pilot.
They dont expect you to be Chuck Yeager, just be able to fly a plane safely, the finer points will be covered in ICUS.