Here's a pretty poster of Sita, wife of Rama, who is kidnapped in the Diwali story by the evil Ravana. Print it for display or cut her out to use as a puppet, perhaps.
Here's a printable poster of a diya, the old-fashioned oil lamp used to light the way back home for Rama and Sita in the story of Diwali, and traditionally lit during the Hindu Festival of Lights to welcome the goddess Lakshmi into homes.
Here's a colourful Hanuman poster to print for Diwali. According to legend, Hanuman, the monkey king, helps Rama rescue Sita from the evil Ravana and defeat him in a mighty battle. Hanuman is worshipped as a symbol of strength, perseverance and devotion.