I know, bleughhh, but at least plan for the first day back so you know what you have to do and you're not feeling all flustered and resentful! 'Winging it' on the first day can often be more stressful as you're not likely to be in full 'Work Mode' yet. You might find after day one you will be geared up again and planning won't feel like such a battle - well no more than usual!
2) Get plenty of sleep.
That 5am alarm will be rudely awakening you on Monday which might be a shock to your system, so you want to do what you can to wake feeling refreshed!
After you have done your quick planning, spend Sunday doing something you enjoy. Make the most of every moment!
4) Plan some treats for yourself.
Give yourself something to look forward to on that first day back. For example, maybe you could plan a yummy breakfast, treat yourself to a Starbucks on your way to work, do something fun on your commute, prepare a delicious lunch or make plans to meet a friend after school etc.
5) Go home early.
I know I will be staying late every day when school gets going, so if you're like me you might also want to ease yourself in gently and make sure the first day is as gentle as possible and go home on the bell, or as close to it as you can! :)