My sister is about to start her first teaching post. She feels well prepared by the university she attended and learned a lot from her teaching practices. She’s confident in her subject and understands all about teaching and learning. “But what,” she asks me, “do I really need to know? What are the golden rules of working in a school?” Well, the following would have been useful to me when I started teaching 25 years ago:

1. Don’t sit down in the staffroom until you’ve seen where everyone else sits, and for goodness sake bring your own mug. If you borrow one, it’s bound to be the deputy head’s; you’ll smash it or chip it and she’ll hate you forever.

2. Don’t offer to make everyone a drink. By the time you’ve sorted out who has herbal infusions, camomile flowers, caffeine-free and extra caffeine, who the china cup and saucer, the World’s Greatest Teacher beaker and the earthenware mug belong to, break time will be over, no one will have had a drink and everyone will hate you.

3. Make friends with the caretaker. Really, really do. Even if everyone else hates you it’s important that the caretaker loves you.

4. You’ll notice that no matter how busy everyone else is, there’s always someone with enough time to go around collecting money for someone’s leaving presentgetting numbers for the staff mealasking for signatures on a new-baby card. Don’t complain about this; you don’t want this person to hate you either.

5. In your first term there will be a virus that attacks only staff members, meaning you lose your non-contact time and have to teach double the number of children. The virus won’t affect the children and they’ll bounce in, full of beans and determined to make that week the one where their attendance is 100 per cent. Don’t moan about this to your colleagues when they return or mention your fever; they’ll just hate you.

6. The day you catch head lice (and you will) will be a Friday, the day before your hairdresser appointment. You’ll need to stay up all night getting rid of the lice, or you’ll have to cancel your appointment and your hairdresser will hate you, or you’ll have to admit to having head lice and your hairdresser will really hate you.

7. You’ll have a child whose behaviour concerns you so much you’ll ask the educational psychologist to come in. The child will behave like an angel on the day of the visit. Don’t complain about this to the psychologist or she’ll mark you down as being hateful.

8. You’ll book a holiday for your first long summer break that costs exactly double the amount of the identical holiday your neighbour booked for term time. Don’t moan about this to your neighbour or they’ll remind you you have 13 weeks holiday a year and hate you.

9. The local press will come to take a photo of you receiving a charity cheque for the school just after you’ve been splattered with paintrice puddingmud and leaves. Don’t ask for 10 minutes to clean up or the press photographer will hate you and you’ll regret it for years to come.

10. No matter what it says on the rota, the new member of staff is always on play duty. Don’t arrange a course, be off sick or attend an emergency when it is your play duty or the staff will hate you.

“Anything else?” asks my sister, a little tremulously. “Yes, don’t take any notice of me. I just had a bad experience 25 years ago. I’m sure schools are much more welcoming now.”

“So your advice would be?”

11. Be yourself, and enjoy being with the kids: everyone will love you.

Maria Corby is deputy head of a special school for pupils with severe and multiple learning difficulties. She writes under a pseudonym