Typically in the first half of an Indian movie you would have a Westernised heroine before the “curse of the second half” hit and out came the saris. And of course vamps were allowed to wear Western clothing all the time! Most of these clothes are similar to contemporaneous fashions in the West, albeit a few years behind at times.
In the late 50s and 60s: Slacks, skivvies. high waisted trousers, pedal pushers, the occasional scarf. The actresses: Mala Sinha, Shashikala, Madhubala, Shakila.