1. Ill-fitting suits
A too-big suit makes you appear childlike: too-small, and you're channelling Hulk Hogan. Neither aspect is good. An ill-fitting suit has never communicated good taste or professionalism. To determine the fitness of your ensemble, consult a guide. If your body type necessitates shopping online or visiting a tailor, do so.
The well-rounded man knows how to iron his clothing - or, failing that, knows at least enough to hang wrinkled items in the shower. If compelled to don a dress shirt twice (or more) before laundering it, hang it up. Never go fishing for an outfit in the hamper.
3. Ignoring stains
The greasy, yellowish ghost of last month's butter chicken will not magically disappear. Shirts with stubborn stains - even if "your favorite", or otherwise "almost new" - belong in the trash. Avoid tragedy. Remember your table manners.
4. Excessive shine
Quality cashmere, wool, or leather (not pants) is always preferable to shiny suits. The same code of subtlety applies to bracelets, rings, and necklaces, which can, on men, easily become too much. If in doubt, follow Coco Chanel's dicta to remove one item before leaving the house. The real shine comes from within, you crazy diamond.
5. Wet hair
Men (and women) who arrive at the office with hair slicked down and sopping often appear rushed, and hence ill-prepared for the day - dare we say, wet behind the ears?
6. Graphic tees
Tee-shirts displaying clever saying, giant logos, and cartoon characters are acceptable in first-year university classrooms and at Crossfit. Elsewhere in life, take pains to ensure that you wear the shirt. The shirt does not wear you.
7. Ill-advised headgear
Corey Hart's opinion notwithstanding, wearing sunglasses at night or indoors is considered gauche, barring a medical condition. Hats, similarly, should generally be removed at the door. Indoors or out, there is no known medical condition that excuses wearing a fedora.