First and foremost, try not to panic out there. I know when I started driving about 14 yrs ago I was a nervous wreck to an extent. I had been an rtd driver and drove air, so I had a pretty good idea how to do it, it is just a matter of learning the area etc...Also in my case I was a militant steward as a part-timer, and knew they woul be looking to disqualify me, but they didn't. I imagine largely because I had made my days as an RTD driver. But donot be afraid to ask the driver of the route you're training on pointers on how to best run it etc...
Pay attention to how the sup's train you in methods etc...if they train you correctly. You'll get it just stay calm and you'll be fine. Keep your eyes moving and always expect the unexpected, and I am serious about that. People will pull out in front of you or behind you with little thought, so use caution.