1. Always tuck your tie into your shirt when you help out at school dinner - expect the unexpected when you look down after the last tray leaves the table. Smiling assassins with yoghurt spoons are everywhere.

2. Say “good morning” to every member of staff or of the school community, and genuinely take an interest in people - mean it. Take an instant liking to everyone you meet and the results will be phenomenal.

3. Don’t walk past any child without saying, “Hello, how are you?” You never know what you might find. A little girl I’d never seen said one day: “What key opens a banana?” Pause - “A monkey!” Brilliant, her wee smile was priceless.

4. Say “thank you” as often as you can to people. To do this, you have to notice what people are doing. Watch people - don’t stare at them, that’s just creepy and weird! - look out the corner of your eye, in as non-weird a way as you can. Be open to how much effort people around you put into their work, and recognise it.

5. Try and earn the right to challenge people by supporting them first. Don’t be soft to the point of mush, but actually try to help people the way you remember being helped by someone.

6. Be brave and make an effort to model the behaviours you would expect from someone you would like to eventually become.

7. Be positive, even when you don’t feel like it. Don’t smile like someone has just trod on your toe and you’re being polite. Try to find a way to see the good over the bad and the ugly.

8. See that parents want what you want for your own children, and empathise. Try having an out-of-body experience and sitting alongside them, seeing things from where they are.

9. Celebrate children as often as you can by noticing the little things. Like a door being opened, a smile, a kind word, anything which you want all of your many children to do. Recognise it so that they keep doing it.

10. Appreciate every effort made, no matter how small from children and staff. Encourage everyone to give their best, then roll your sleeves up and say “Who’s coming with me?”, Jerry Maguire style - minus the goldfish.

11. Do the best you can with the information you have at the time. Don’t faff about, make the decision and take what happens on the chin - you’ll develop a rugged exterior.

12. Make a decision when the opportunity arises and be confident in your own ability. If you doubt your powers, you give powers to your doubts. (Ben Stiller in Mystery Men told me that.)

13. Trust people, be honest and take responsibility for the decisions you and your staff make. Don’t walk along a corridor with your back to the wall - you’ll knock posters down for a start.

14. Be resilient and talk to yourself positively as often as you can.

15. Do the ugly work first.

16. Be relentless and work as hard as you possibly can. Be spent when you walk out the door - then recharge on the way home.

17. Remember children’s names - all of them - and say sorry when you get them wrong.

18. Be willing to be the lead learner - don’t be precious about sharing your learning or you can’t very well tell off four-year-olds for not doing the same thing.

19. Don’t be lazy: cut the fish cake, open the ketchup sachet, hold the door, smile, walk the corridor, stand at the gate on time (with enthusiasm) - and wait for the miracle to happen. It will - I promise.

20. Forget work issues as soon as you get home to your wife/husband/partner/children, and appreciate how you are the luckiest person in the world.

Nicky Murray is headteacher at Burnside Primary School in Carnoustie, Angus, in Scotland. He tweets @BurnsidePS