1. Don't. It's too hard. Write about wizards or zombies or bad-ass girls or something easy like that.
OK – you're pig-headed and are going to try anyway. So:
2. Remember that a good football novel has to have the same ingredients as any other good novel: drama, convincing and interesting characters, a strong story-line, and some kind of magic in the writing. That means you'll probably be writing a story around football rather than about football. A ghost story, maybe, or a murder mystery or a story about a family bust-up, in which football plays a part. You need to capture readers who might not be that interested in the game.
3. If you're writing for younger readers, it doesn't follow that you have to write about kids playing football. Young people watch top-class Premiership and international games, and that's the kind of football they're interested in reading about, not an underdog team of Year 8s winning the Junior Vase on a damp Sunday morning. There aren't any 13-year-olds playing in the Premiership. Yet. (I'm talking about physical age here, not mental.)
4. Keep "live action" sequences to a minimum. It's extremely difficult to describe interestingly what happens on the pitch. Thousands of journalists write millions of words every week trying to do it, so your chances of avoiding cliché are very slim. And you're trying to write fiction, not a match report. But seeing as how describing play is tricky to avoid if you're writing a football story, the following two tips might come in handy.
5. Try not to write action as if you're a TV camera following the ball. If you go to watch games, you'll know that lots of interesting stuff happens "off the ball" – on parts of the pitch (or even off the pitch) that are also off-camera. Football is a bit like chess: it's not just the piece being moved that matters, it's also the effect that move has on all the other pieces. (Call me weird, but I'm always kind of interested in what keepers are doing when the play is at the other end.)
6. Live action scenes should connect with the rest of the story, not be separate episodes written for fans. For example, in The Penalty Paul Faustino watches a video of a game not because he's a sports journalist but because he's looking for clues as to why a young player gets taken off and then disappears from the stadium, presumably kidnapped. You also need to think about point of view, that is, who's describing the action. Is it a spectator, someone watching on TV, the manager, a girlfriend, or someone playing in the game? (If it's the last one, see Tip 8 below.)
7. Don't worry too much about being "realistic". Everyone who sits on a sofa watching Match of the Day is a top soccer expert, as you know. So if you start to worry about such people reading your story and saying "That'd never happen" you're going to freeze up. You're writing fiction, and your characters can do whatever you need them to do. Another example: in Keeper my hero, who is also the narrator, is incredibly articulate and a skilful story-teller. This is highly unlikely. We all know that players who are geniuses on the pitch often have trouble stringing together ten words that make sense. They'd probably find it easier to talk about their tattoos than describe what they did in a game. I decided that didn't matter. I needed a footballer who knew how to tell a story, because it was the story that mattered more than anything else.
8. Unless you're an absolute master of imagination, you probably shouldn't try to write a football story if a) you don't love the game and b) you've never played it. It really helps if you know what it feels like to spend ninety minutes in a rain-soaked shirt on a cold night running up and down the pitch with a damaged ankle, working your ass off, being fouled, being cheered or jeered at, and losing. Or what it feels like to hit a ball and knowing, really knowing, that you've hit it with exactly the right weight and at exactly the right angle to score.
If neither a) nor b) apply to you, go back to Tip 1.