Accessorize with dark shades and neutrals. You’re already wearing a show-stealing suit, the last thing you’d want is for your accessories to distract from that. You want your ties, shoes, lapels, etc. to complement the outfit, rather than draw all attention. Think in terms of brown, tan, beige, and black. This isn’t to say that other colors are doable. If you want to add more color, it is possible, but requires a more in-depth understanding of color combination.
Fit is king. We’re sure you know this already, but it always helps to get down to the basics. Unless you’re buying bespoke, most suits will need tailoring. Learn how to talk to your tailor, and make sure your fit is pristine.
SOURCE: THE GENTLEMANUAL