British cut suits are heavily tapered at the waist, and suit someone who has a athletic build, as it shows off a larger chest.
Italian suits tend to have a reverse triangular shape to them, but are well fitted.
American cuts are based on the puritan mindset of the american consumer, and tend to have a boxy, somewhat loose fit. This reflects the larger american size and the willingness to look less ‘polished’
Vents have none, single and double. Double vents are more suited for someone with a larger posterior, as it doesn’t bunch up the suit. Also, they look a little more classical, in keeping with the military influence that created the suit in the first place
Single vents are a standard nowadays, and are a safe bet for normal body types.
No vents are ballsy, tend to show more wear in the seat after use, and tend to find their way more into italian cut suits. however, if you can pull it off, you probably have a very slim build
Lapels you’re pretty bang on for, just remember, notch look more conservative, and peak tend to be a detail to show more flair. Again, Italians are the masters of exploiting that feature, and it lends well to wider knots and collars.
For cuffs, the standard is 1/4 inch(collar and cuff), but depending on how much of an accent you want, can go all the way to a full inch.
French cuffs are a more formal look. if you want to dress them down, links don’t have to be metal, but can be knotted cloth. Mother of pearl links are the classic, and silver or gold covered metals are somewhat less formal, and just as dressy. Leave these subtle, you don’t need funky, as there are other places to show off than here. Have the metals match if you can, it shows you respect the attention to detail.
single and double barrel cuffs are the standard, with one or two rows of buttons. use the outsmost button if you need to wear a watch, otherwise go tight as is comfortable. with any shirt, you want the cuff to touch the first knuckle on your thumb when arms are at your sides.
Pants have pleats and flat front. Pleats are better looking on large people, but any more than one will make you look like a clown, and are a throwback to a faraway age of useless. Flat front tend to look the best on most types of guys. Cuffs on the pants are a very old fashioned look, and unless you want that look from the 50’s than it’s best to stay away.
As for length, a small break in the ankle is the best, where the back would touch the ground if you weren’t wearing shoes. You take take it a little lower if you want to tone it down, but be careful, you look shabby very quickly. Also raising it up is good if you are into colorful and exotic socks, or an ankle boot, if you want to show it off. This is a very ballsy type of thing, and not everyone can pull it off however.
and if you can see what’s in your pockets, they shouldn’t be in your pockets.
Ties, standard are 3.5 in with skinny at 2.5 and the wide british style 4.5. There are the sub 2 inchers, but the short answer is ‘no’
don’t match your pocket square to the colour of your tie, a standard white one is sufficient, don’t stray until you’ve worn one for a while and know what you’re doing. puff is a classic, and shows a touch of artful dishevelment. single, double and triple points are good as well, or square for a classic look. There’s dozens of folds, time to experiment.
Tie clips are old fashioned, and it’s hard to do it without looking like you are selling televisions, same for the collar clip.
The collar will vary from wide to narrow tapers. wider neck, wider taper, and the reverse are safe, but don’t feel like it’s a must. the knot should fill the space between the two, so know your knots.
single Windsor and four in hand are good for narrow knots. Windsor is better for making a nicer triangle. a double Windsor takes more practice, but will look better, plus makes more fabric if you need a larger knot.
bottom of the tie should touch your belt buckle, barely.
the buttons on the sleeves are functional, 3 or 4 is normal. It’s a detail that’s a throwback from the military styling of the original suits.
belts should be thin (unless you are really tall, then you have more leeway) match the leather in your shoes. play with the buckle, but don’t get too blingy, it looks tacky.
socks should be long enough to never see your exposed leg, no matter how you sit or stand in a suit. Here’s another place where you can go wild with colour and style. just remember, the standard wall mart socks will look out of place.
On watches, leather strap is formal, metal is casual, ceramic ones are still arguable. thinner the better for the watch face. If it’s digital, save it for your t shirts
a double breasted suit looks better on a man with girth, and has a nautical feel to it.
three buttons are old styles from the 90s and unless you are very tall, are not very flattering
two buttons are classic, and you cannot go wrong.
Also, the rule for buttons is sometimes, always and never. with two buttons its just always/never
if you see a button under your lapel, its another throwback from the military, back when the collars were put up, don’t use it, and don’t be worried about the button hole on your lapel either.
shoes should be just as expensive as your suit, if you can. an oxford is classic, loafer is ok in the summer with lighter suits, and a boot if you feel a little ballsier. shinier the shoe and pointier the toe, the more formal the footwear. with a formal suit look, this is where the ‘never mix black and brown’ come into play, same as blue and black.
and for altering, shoulders are the part that ‘has’ to fit, everything else can (and should) be altered to fit.