There is but one knot: the Doube Windsor.
The jacket goes off in the car, and at the desk. Whilst moving about in the office, it is supposed to be on, except maybe for a quick visit to the loo.
Suits are supposed to be in one colour. Combinations are not appropriate business attire. Suits come in two colours: marine and grey. Optionally, a suit may be pin-striped.
Dress shirts do not come in short sleeve versions. They have double cuffs (to be worn with classy cufflinks), wide spread collars that use those insert-stiffen-thingies (UncleBeer knows what they’re called), and come with no shirt pocket. They are either solid, striped, or slightly checkered. Possible colours are white, light to medium blue, and light pink.
Shoes are black, and have laces, not belts or buckles or whatnot. The soles are made of leather, not rubber. The sole has a Goodyear-stitch. On a trendy day, ankle-high shoes may be worn. There is an ongoing debate about whether or not Brogues are appropriate. I’m modern, and say thay can be. If black.
Socks are black, gray or blue (see suit: match it, or be safe and match the shoes: i.e., black). Maybe they are checkered, but only if they’re real Burlingtons.
Ties are solid, striped, or have a modest pattern. There are no other ties. There are stories doing the rounds about ties with Disney figures on them, but those are likely Urban Legends. Tie colours are the only thing about your attire that can be bright: flaming yellow, bright red, metalic blue, do it. It’s your only chance of making the suit “speak”.
The belt is always worn (dress pants without a belt! Feh!), it is black, and it has a silver buckle.
Tie pins are strictly forbidden, as are armbands, necklaces, earrings, and facial piercings.
Welcome to the world of banking. I don’t mind having all these fancy clothes, I really don’t. But I’m glad that I can go “casual” now, because of the hot summer weather.
But if you’re gonna wear a suit, do it the right way, or not at all.