A three piece suit is a versatile look, but a bold statement. Since the combination of the three piece already stands out, keep the shirt shirt and time simple. This allows for balance. Here, I went with a navy blue suit but checkered vest. The vest has both burgundy and navy accents which connect perfectly to the suit, loafers, and tie. The pocket square has the same effect, complimenting elements of the look.
Now for the fit. The cut of a garment is crucial!
The vest is the focal point. It should be fitted and sit right on the belt. The jacket should also be fitted. Giving a clean, tailored look. And of course, the pants. Treat them as if they are regular fitted suit pants.
Now we all can't afford custom suits, but we can buy the right size/fit and also spend a couple extra bucks at the tailor. Keep for a clean, tailored look. It speaks volumes!