The snazziest thing you're going to be able to do is a Don Johnson thing, as shown in the picture rdowns posted. White cotton suit separates, casual shirt open 2 buttons in a solid neon color. Note that in the 80s you can wear pink as a dude. Dock shoes with no socks. Ray-bans, everywhere, always.
You could go as an 80s business dude. This will require a style of dress shirt that may be hard to find these days: It's blue with white pinstripes, but the collar and the french cuffs are solid white. The collar must button down. If you can find a pair of silver dollar cufflinks, score. Suspenders are mandatory. Khaki slacks, shoes that look as expensive as possible, hair slicked back. As long as you're not a kid who'd get in serious trouble for suggesting drug use, a little dusting of talcum powder on the upper lip will totally complete the look. This is a costume you could play in-character by talking really fast, laughing inappropriately and always talking as if the fate of the world rested on whatever you're saying at the moment, even if that happens to be excusing yourself to to the restroom. Watch the first half of ROBOCOP or the
Futurestock episode of Futurama for a good parody of 80s business guys.
A Michael Jackson thing will also be popular, but good luck finding the thriller jacket and glove nowadays. I seem to recall a pathetic attempt to reintroduce parachute pants within the last couple of years, but thankfully the retro loop isn't completely stupid and vomited those right back out. You might be able to find a puffy silver jacket. There was a brief time in the 80s when people decided it was finally the future so it was time we all started wearing things like silver clothing and jumpsuits. I think the end result was that science fiction people finally said "oh. duh." and stopped putting their characters in such miserable clothing.
Typical 80s casual involves a t-shirt (neon, of course), an Izod knit shirt or a button-down-collar long-sleeve shirt, acid washed jeans and white Reeboks. Unless you're wearing a t-shirt, your shirt MUST have an embroidered logo on it. Wear a Members Only jacket, but don't make the mistake of looking for a leather one. Leather existed, but almost all of them were fabric.
Possibly the simplest thing you could do is the REALLY casual. Find a pair of Hawaiian-print Jams board shorts, a Hypercolor t-shirt (good luck) or a neon or tie-dye t-shirt. Wear Tevas or white Reeboks with no socks.