The way a suit fits is more important than the fabric, the pattern, the designer, even the color. It’s the fit that gets people to notice you – spoiler, it’s a good fit that reflects well on you, a bad fit . . . forget that 2nd date.
So how can you tell if a suit is fitting you well? No, you can’t button the jacket and pull to see how big it is (that just There are two parts to consider; that which is set in the factory and you can’t change, and, that which your tailor can adjust.
Let’s dispense with the easy part: Tailor’s can lengthen or shorten sleeves, hem pant bottoms, take in or let out waists, clean up the seat, adjust collar rolls (roll of fabric behind the neck), taper or let out the sides of a coat.
But, a tailor can’t change the way the shoulder fits (and if he says he can, be very, very skeptical). Taking a bolt of cloth from a limp piece of fabric and molding it to fit your chest and shoulder well is what the big designers get paid to do. It’s the junction between your shoulder, your arm, and your chest that is set in stone in the factory.
As you try on your next suit, gaze at yourself in the mirror. Look closely at the shoulder head – is it sitting right where your shoulder stops? Is it too tight (arm/deltoid pokes out a bit, top of the arm of the suit is sucked in and not hanging free?) or too loose (there’s an overhang from the shoulder of the coat to where your arm actually is)? Or, is it just right – hugging the shoulder and arm, the shoulder ending where yours ends.
Now take a look at the top of the shoulder. Ideally it looks crisp, straight, and clean. No waves, no divots, no problems. And this, my friend, is a good fitting, classic shoulder.