Go With a Tuxedo
There’s only one proper way to go to a black-tie event: a tuxedo. It’s not an ordinary black suit. Instead, it has unique lapels, which make it look more formal. However, that doesn’t mean you must wear your regular black tuxedo.
Instead, you can add some distinction, like going with a dark blue or red one. Also, if you could find a tuxedo with velvet, then you’ll look even better.