Dwell on the positive
Being a newly qualified teacher can be a daunting experience: teaching practice was hard enough, but now you're doing it for real and being paid for it. Where do you start?
Hopefully you will have been given some idea of what topicstexts you should be starting with. If you get the chance, check out what you have planned with a member of the department before term starts. Don't be surprised if your plans don't go swimmingly well: it's enormously difficult to plan for groups you don't know so be prepared to adapt or abandon.
Be prepared in yourself. It is unlikely to be easy. Often you will be starting in a new town, organising for your fridge to be delivered and trying to con the kids into believing you've been doing this for years.
Make sure you spend time in the staffroom. Spending your lunchtime in your classroom may get the marking done but you will be cutting yourself off from an enormous pool of experience, support and good ideas for dealing with obnoxious Johnny Herbert in 3B. If nothing else it may boost your morale to know that everyone else has the same problems with him.
Go in with the right attitude. Aim as high as you like, but don't allow yourself to be gripped with despondency if things go wrong.
As an NQT you are not expected to get it all right the first time. Assign your mistakes to the file marked "learning curve experiences" and dwell on your successes.
Try to plan your own time as well as your lessons - decide on when you're going to do your markingplanning and try to stick to it. Make time for yourself. Sitting in front of the television can lead to the "beckoning briefcase syndrome" (I'll mark all evening but because the television's on I'll call it relaxing). Get involved in some kind of school-unrelated activity - remember, there's a whole real world out there: lose touch with it at your peril . . .