Some excerpts from the Formalwear chapter of The Encyclopedia of Men's Clothes:
Tuxedo Jacket: Peak lapels in satin, silk or grosgrain, single breasted, one button is traditional, piped or double besom pockets (avoid flap pockets), no vents or minimal side vents.
Dinner jackets are the same length as suit jackets, but Tailcoats have tails that should be no longer than back of your knee.
The waist of the trousers and the bottom of the shirt pleats must be covered by a cummerbund or waistcoat or Double-breasted dinner jacket, which is, of course, never unbuttoned.
Lapels: Peaked or shawl lapels are both appropriate, the notched is not. The peaked lapel, single-breasted dinner jacket is the most correct since it's derived directly from the original tailcoat, and the shawl has origins from the smoking jacket.
Shirt: White or Ivory with wing or straight collar and French cuffs, pleated front you'll use studs that match your cuff links to close the front of the shirt. Wing collars are more appropriate for tailcoats but are acceptable for any formalwear.
The formal shirt will have a pleated front (to the waist only, so that it doesn't buckle when you sit down) - that's the reason the waist is always covered with either a cummerbund or waistcoat.
The shirt pleats (not ruffles!) will be refined; Â¼ to Â½ inch pleats will do nicely. Fewer pleats are more sophisticated than many. An alternative is pique or waffle weave fabric on the front of the shirt.
Like any dress shirts Â½" of "linen" should be exposed beyond the jacket sleeve. This finishes off the look plus gives guests a chance to check out your fabulous cuff links.
Cuff links and matching Studs - not buttons are used to close the front. When you buy the formal shirt you'll notice that the shirt is kept closed by buttons sewn on a ribbon. When you open the shirt remove the buttons on the ribbon. You'll use your matching studs. Cuff links and studs should be quiet and elegant in style.
Tie: Black silk or satin in either thistle or batwing style and tied yourself!!!
Trousers should match the jacket, be pleated, held up by braces only, with a seam up the outside leg (derived from military formal dress from the officers leg braid) of satin, silk or grosgrain. One leg seam for black tie and two for white tie and tails. The braid should match the fabric on the dinner jacket lapels.
And NEVER cuffed!
Shoes: Black Patent leather dancing pumps with ribbed silk bows are the most traditional. Formal shoes can also be shined leather or velvet. Velvet pumps are most appropriate when you are hosting a formal evening at home!
Oxfords (lace up) are fine, especially in an emergency. If you're going to wear oxfords, the best choice would be a plain toe or cap toe.