Smooth Operator

A properly fitted tuxedo jacket lies smoothly from shoulder to shoulder across the back, with enough room for comfortable arm movement (have your groom-to-be give you a hug to gauge his comfort level). If the shoulder padding extends beyond his shoulders, the jacket is too big; if the jacket creases in the back, it's too small.
Vested Interest
Formal dressing requires that the waist of a man's trousers never be exposed. If your guy opts to wear a vest, he should leave the bottom button undone (the portly King Edward VII started this trend at the beginning of the 20th century). If your groom chooses to wear a cummerbund instead, make sure the pleats face up.
Com-pleat Package
If your fiancé is tall and slim, flat-front trousers are a great pick; they're cut slimmer through the legs and hug the hips nicely. Traditional pleated pants have a more relaxed fit, making them ideal for huskier body types. The pants' crease should cross the middle of his kneecap, and any pockets should lie flat against the leg. if they gape open, he needs a larger size.
Great Lengths
The standard length for men's formalwear trousers is approximately one and three-quarter inches from the floor (with shoes on); the pant legs should break on the top of the shoe and angle slightly downward in back.
Hot Under the Collar
If your guy complains that dress shirts are uncomfortable, his shirt may simply fit poorly. Have him do the finger test:
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