You invent a catchy title, you expand the boundaries of a juxtaposition as far away as your imagination would allow (autism, violence), you write in a gimmicky way that is also true to the authentic feel, you try to cram it all into a style that would be readable on a bus or a train on the way to work or back home. You make sure Ian McEwan likes it (arguably the trickiest part of it), and there you have it. The Curious Incident Of The Dog In The Night-Time.
People suffering from A.D.D. are more than welcome. As is everyone else. Incidentally, Mark Haddon’s novel happens to be really good. Almost a shame, all things considered.