Im doing a duet to 'Oh what a night' in my school dance show. My partner and I need ideas for a costume. Help!?

The dance is quite jazzy, fast, and sort of hippy, if you get me. And, errr.... well the costume needs to be kinda sixties style. Also, you need to be able to dance in it, and we need TROUSERS, or shorts, something that you cant see up. Like a skirt. lol xx (we're doing kicks and lifts).