| | Re: 1st day jitters
As everyone else has said, don't worry. The students will likely be more nervous than you (although they may not show it).
Something to consider in terms of activities and preparation, always plan for more activities than you'll need. It's easier to remove some games/icebreakers, or even shorten and simplify them, than it is to come up with extra ideas on the spot... especially if you're new and nervous.
Good luck and let us know how it all goes!