We’ll start with the easy part: getting the right size.
This will serve you well whether you’re buying handmade Italian imports or off-the-rack at Sears.
Fashion has widened and narrowed ties back and forth over the years. Don’t bother keeping track.
A good necktie is right in the comfortable middle. 3 1/4″ is ideal for most men (the width is measured at the widest point, before the tapered tip if there is one).
If you happen to be built particularly broad you may want a little extra width to keep things proportional, on up to 3 3/4″ or so.
Similarly, very slender men can go down to about 2 3/4″ without looking like they’re wearing a “skinny tie.”
Ties without any taper (a somewhat old-fashioned style these days) should be a touch skinnier, around the 2 3/4″ range as well.
To quickly judge width in a store I use the dollar test – since the USD is approximately 6 inches long, fold it in half and you have a 3 inch ruler. Then you can quickly see approximately what width tie you’re about to buy. My sweet spot for my body build/style requirements is 3.25 inches. Yours may be bigger or smaller depending on taste.