Most men buy shirts by collar size and hope for the best. There are five checks that take ninety seconds in a fitting room and decide whether a shirt will look good for years or feel wrong from the first wear. Here they are, in the order they matter.
1. The shoulder — buy for this above all
The shoulder seam must sit exactly where your shoulder ends and your arm begins. Too far in and the shirt pulls across the back; too far out and the sleeve head collapses in a soft fold down your upper arm.
This matters most because it is the one thing that cannot be corrected cheaply. Re-cutting a shoulder means dismantling the sleeve, the yoke and the collar — more work than the shirt is usually worth. Everything else on this list is adjustable. So choose your size on the shoulder, then fix the rest.
2. The neck
Button the collar. You should be able to slide one finger comfortably between collar and neck — no more, no less. Tighter and it will be unbearable by noon and will visibly strain when you knot a tie. Looser and the collar gapes and the tie sits away from the throat.
Remember that cotton shrinks slightly on first wash. A shirt that fits perfectly at the neck in the shop may be marginally tighter after a month. Buy accordingly.
3. The sleeve length
With your arms relaxed at your sides, the cuff should end at the base of your thumb — the point where your wrist meets your hand. Under a jacket, roughly a centimetre of shirt cuff should show beyond the jacket sleeve.
This is the most commonly wrong measurement on a ready-made shirt and the easiest to correct. Never reject a shirt that fits at the shoulder because the sleeve is long — that is a short alteration, not a reason to walk away.
4. The body
With the shirt buttoned and tucked, you want enough room to sit comfortably and no more. The traditional test: you should be able to pinch about five to eight centimetres of fabric at each side of your waist. Much more than that and it will billow when tucked; much less and it will pull between the buttons when you sit.
If the shoulder is right but the body is loose, that is a straightforward taper — arguably the single most transformative alteration available on a ready-made shirt.
5. Fabric and collar — the choices that are actually yours
For Chennai, fine cotton wins: poplin for crispness, voile and lightweight weaves for the hottest months, twill when you want a bit more body, linen blends when comfort matters more than a sharp press. Avoid high synthetic content unless the wrinkle-resistance genuinely outweighs the heat.
On collars: a semi-spread suits almost everyone and works with or without a tie. Wider spreads flatter narrower faces; point collars flatter rounder ones. Button-down collars belong to casual and smart-casual, not to a formal suit.