4. Don't Wear Shirts With Coloured Panels
Jonah Hill makes his entrance in the movie in classic-yet-chic style. Well, at least he'd like to think he did. Sporting a frankly hideous shirt in a variety of pastel-coloured panels, Hill's character 'Donny' propositions Belford in a greasy spoon café - asking to become his partner. Partners they become, and their success skyrockets to limitless booze, drugs and women - but thankfully also a collection of bespoke and tasteful suits. Our advice would be that if you're looking to make a business pitch to a man in a three-piece, try and sort out your colour coordination first.