A Fifties costume idea suitable for Halloween or a theme party is that of the Rocker. Rockers were a British subculture of that era and, although sometimes also known as greasers, the latter term had a different meaning in Britain to North America.

The getup of a rocker was heavily influenced by motorcycle wear, as motorcycles were an important and, indeed, focal part of the subculture.
The Body
The principal item was a leather motorcycle jacket, which would be heavily decorated with such things as metal studs, patches and pin badges. Other worn items were T-shirts, leather caps, Levi’s and Wrangler jeans and motorcycle boots. An alternative to the boots would be brothel creepers, a type of suede shoe with a crepe sole.
The Head
Accompaniments worn whilst riding a motorbike would include an open faced motorcycle helmet and aviator goggles and a white silk scarf.
For the hair, a pompadour hairstyle held in place with Brylcreem, as was popular with a number of rock musicians of the era, would be the hairstyle of choice.
The Accessory
A true rocker would also have a specially customised motorbike; this is less than practical for a costume. During the 1950s, rockers also clashed with other groups such as the Mods. Perhaps a toy motorcycle would stand in for this.