Meg Rosoff is the prize-winning author of How I Live Now, Just In Case, What I Was, The Bride’s Farewell and There Is No Dog. Her new novel, Picture Me Gone, will be published in October.

I spent fifteen miserable years in advertising and when I finally left, had nothing to show for it except a few ads no one remembered — and a flat bought on my meagre salary in 1991.

I was fired a lot, for insubordination and general disgust with the people and the process, though mainly with myself, for not having the courage to quit and do something worthwhile.

Once I started writing novels, however, I discovered that those fifteen years hadn’t been entirely wasted. Which was a relief. In retrospect I think of it as a medieval apprenticeship, the kind where they chain you to a bench and force you to do lowly things for fifteen years until you’re competent enough to make a shoe.

And so here are a few things I learned in my apprenticeship.

1. READ.

Bestsellers and obscure new writers, 18th, 19th and 20th century writers as well. Shakespeare. History and fiction, memoir and picture books, everything that’s really good and occasionally some stuff that’s really bad. Ideas come from everywhere, and besides, if you’re not interested in books you shouldn’t be writing them.

2. Marketing is important.

If there’s no market, there’s no money (and writing is, after all, a job – a better than average job, but a job nonetheless).

3. But…ignore the market when you work.

People writing solely to make money can always be picked out of a criminal line-up. They look cheap, sweaty and desperate. The rest of us just look desperate.

4. Know how to write.

Really, it helps.

5. Spend time thinking.

Writing’s only about 20% of the job. Sometimes less.

6. There are no rules.

Your job is to break the rules.

7. Be wise.

Know more than your audience about something — anything.

8. Cut to the chase.

The average attention span of the modern human is about half as long as whatever you’re trying to tell him (or her).

9. Get a life.

Breadth of knowledge is good, emotional depth is even better.

10. Lie about everything except passion.

Chairs can talk. Pigs can fly. But if you don’t care about what you’re saying, no one else will either.

11. Listen to what other people have to say.

If fifteen people say that your shoe is dull, heavy and cloddish, it probably is.

12. But…when a publisher says ‘that sort of book doesn’t sell,’

don’t throw it away. No one knows what sells. Until it does.

13. Don’t worry about your connections (or lack thereof).

Anyone who’s really good will get there. Blind, dogged persistence passes the time between now and then.

14. Edit ruthlessly.

Do not fall in love with your own prose. God invented the delete button to help you.

15. Keep at it.

It’s a long game (ask Mary Berry about her 30 years in the wilderness). No one has an easy run from beginning to end.And that goes for life as well as writing.

And that’s more than enough advice for one day.

This article was originally published at megrosoff.co.uk, reproduced with permission. Thank you to Meg for allowing us to share her work. For news and updates from Meg Rosoff follow her on Twitter.