#1 Wearing Suspenders And A Belt Suspenders hold your trousers up. So do belts. Therefore, you don't need both. More importantly, you don't want to wear both – not only is it an obvious fashion error, but it also creates three sides of a square around the middle of your body. Frankly, it just looks a bit weird.
#2 Incorrectly Matching Your Socks And Pants The temptation to match your socks to your shoes is an obvious one, but it's the wrong idea. When it comes to socks, there are two ways a man can dress: 1. Subtle socks that blend in with the color of his pants 2. Bold socks that make a statement
#3 Popping Your Collar Two errors kind of rolled into one here because they're related, and they're both awful. Your shirt collar should never be “popped” – the points should point downward, and the whole thing should be folded over evenly.
#4 Buttoning Your Suit Incorrectly Buttons are an easy place to make an error because the rules are different for different garments. Jackets are never fully buttoned unless they are double-breasted jackets. Two-button jackets usually button at the top button, and three-button jackets button in the middle.
#5 Mismatching Belt & Dress Shoes As a general rule, dress shoes must always match your belt. They don't have to be made of the same leather, but no brown shoes and black belts, or vice versa! The more casual you get, the more flexible it becomes, but mixing black and brown is always going to be a beginner's mistake.