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. READ .  Bestsellers and obscure new writers, 18 th , 19 th and 20 th 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. 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). 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