The poly is nothing to fear. I went in with all these wild thoughts and ideas, and I came out with a "that was it?" mentality.
If it's anything like my dispatch hiring process, you'll probably be the same way. As long as you were honest with them from the start, they already know anything that might disqualify you. If that's the case, and they're offering to conduct the polygraph, it should bode well as they haven't found anything significant enough to disqualify you so far. Why waste the time and money to have the polygraph done if you're not worth hiring?
Just relax and go at it with an open mind. Get good sleep, a nice meal, and think positive. It's ok to be nervous when taking one, but you should only fear it if you're hiding something.
The psych was fun for me. I laughed at a lot of the questions on the written portion and had a rather enjoyable time when I actually sat down with the Doctor.
My oral board went by really fast and I thought I bombed it, as the two people in front of me were in the room for 20-30 minutes. I was out in less than 10. Just be yourself, that's all I can suggest.
I did all of this when I was 18 for a metro atlanta county police department. I go thursday for my oral board for an Officer position with a department in South Carolina, so hopefully my own advice will hold true!
GOOD LUCK!!!
"You're abrasive, an idiot, a liar, a liberal and fool. I'd call that fairly accurate. Wait a minute. I think I could have just called you a Liberal and that would have included all the others ..." ro56 @ realpolice, 2006.
RIP Sergeant Reeves and Officer Gilner