This is an indicative itinerary which can be fully customised for you

Your journey begins in the beautiful state of Kerala justly called God's Own Country. The land of the quiet Backwater and lagoons beckons travelers to enter the gateway to heaven. You arrive in Cochin City, also called the Queen of the Arabian Sea. Here you can visit the famous Dutch Palace and the Jewish Synagogue. In the evening you can enjoy a sunset cruise.
From Cochin you fly to Chennai. Particularly charming features of this city are its allegiance to ancient traditions, no matter how modernized it has become, and its willingness to spread out further rather than develop into a multi-storey concrete jungle. You can plan an excursion to Mahaballipuram where you must visit the exquisite shore temples.
Your next stop is the emerald state of Goa. You have a leisurely three days in Goa to unwind on the sunny beaches or even better, get a relaxing massage. You must experiment with the Goan cuisine, which is an interesting blend of Indian and Portuguese food.  From Goa you fly to Thiruvananthapuram. 
Polite Note: Package starts on a Monday, as flights are not available on all days between some sectors: