Hi Anshul. The itinerary that I am posting is pretty generic and can be used.
Day 1- GUWAHATI – CHERRAPUNJI. You can find cabs at the airport which would take you to Cherrapunji.
Day 2 - CHERRAPUNJI – SHILLONG
Day 3 - SHILLONG – KAZIRANGA
Day 4 - KAZIRANGA TO DIRANG
Day 5 -A whole day for Tawang sightseeing
Day 6 - TAWANG – BOMDILA
Day 7 - BOMDILA – TEZPUR
Day 8 - TEZPUR - GUWAHAT
Day 9 - Take the flight back home.