You can decide when to travel, the level of service and the hotel standard. Pack in as many activities and locations as possible, or incorporate some relaxation and free time to explore on your own terms.
Pick you from the airport then move to Kandy, on the way visit Pinnawala elephant orphanage, evening cultural dance show. Stay in Kandy.
Day 2
Peradeniya / Colombo
Morning visit the temple of the tooth, Peradeniya botanical garden then move to Colombo. Evening visit pettah market, have a nice walk in the gall face beach, and try some local dinner there. Stay in Colombo.
Day 3
Negombo
Move to Negombo, visit the fisherman village, Negombo city then drop you the Airport.