Havelock/ Neil islands are directly connected to Port Blair by Ferry.
I first went to Havelock island and reached there around 14:00. There are four beaches at this island. I was staying at resort near Vijaynagar beach. This beach is quite and calm and not many people go there. After seeing this beach, went to Radhanagar beach around 15:30. One can spend good amount of time here either in water or on land. People really enjoy playing in water here. There is one place very near to beach where you can have buffet to fill your belly. This beach is also sunset point of Havelock island. You complete your first day tour here.
Next morning, I went to Kalapathar beach (Sunrise point) to enjoy the beautiful view of rising sun. After spending around 60 minutes here, went to Elephant beach. One can reach there via two ways. One way is to hire boat near Jetty and other is by trekking. Trekking is done through forest and hence it has an opening time (7:30 to 13:00). One can do water sport activities at Elephant beach. You complete the fourth and last beach of Havelock island here. Now, move to Neil island.
There are four beaches (Sitapur, Bharatpur, Laxmanpur-II, and Laxmanpur-I) in Neil Island. Sitapur is sunrise and Laxmanpur-I is sunset point. This island is very small and beaches are nearby. Water sport activities can be done at Bharatpur beach. There is a natural bridge at Laxmanpur-II beach. One can see various types of fishes and other small sea animals at this beach. The sunset point is really very beautiful in evening as sun slowly goes down in the sea. One day is enough to cover all these beaches.
P.S.: Scooty is available for rent at these two islands.