He joined advertising as a copywriter first with Shems Combit and then TBWA Anthem, and later he joined Contract Advertising, Delhi, where he worked under Pradeep Sarkar, who was then a creative director at the agency. Screenwriter Jaideep Sahni was also one of his colleagues, who later penned Khosla Ka Ghosla's story, screenplay, dialogues and lyrics.
In 1997, he left Contract to launch his own company, 'Watermark', with two ex- NID friends, making ad films and promos for Channel V and MTV. Eventually he moved to Mumbai, and shot his debut feature film, Khosla Ka Ghosla (2006) starring Anupam Kher and Boman Irani, in 45 days. The film went on to receive not just accolades for him but also a National Film Award amongst others, and brought him in the list of new filmmakers who were bringing about a marked shift in Bollywood themes under new filmmakers.
In 2008, he co-wrote and directed his second feature, also set in his hometown Delhi, Oye Lucky! Lucky Oye!, with Abhay Deol and Paresh Rawal, it was premiered at the IFFI, Goa, and also at MoMA, New York. Commercially it was released in the 26/11 weekend, though it went on to become a sleeper hit; later New York Times described it as "a breezy mix of satire and realism", and the film won three Filmfare Awards.
Dibaker continues to make ad films under his new banner, Freshwater Films, this includes recent films for Promise and a series for Horlicks.
In 2010, he directed India's first digital film, Love Sex aur Dhokha (LSD), inspired by the famous 2004 DPS MMS scandal, produced by Balaji Telefilms.