Black wool suit, single or double breasted, with a black cotton dress shirt with all-black cufflinks, with all-black tie clip, with an all black silk tie.
Make sure you are wearing "gum shoes" aka rubber-soled leather dress shoes so they are silent when you walk.
Combine the look with either an inconspicuous all-black briefcase.
Also look into black-framed mirrored aviators, or wrap-around mirrored sunglasses if you don't want people to see the sides of your eye. Make sure it is a one-way mirror from the outside lens.
Wear all black tactical shooting gloves if you want to keep germs off of your hands.
If you really want to stand out, instead of wearing the mirrored sunglasses mentioned above, wear mirrored welder goggles. Like these:

Also get an all-black watch or pen that can record audio and video.
Do not forget the all-black tactical pen.

And a night guard:
