Go to Goodwill. Get tight leather pants, and a leather jacket or denim jacket, and load your hair with hairspray and makeup to pull off that 80s hair metal look. Or you could just get neon colors with spandex. In general you need to look as rediculous as you can.
the closest you can get know to find a large group of people dressed like they think they are in the 80's is at your next electro concert in your town.