Mangalore can be covered in 2 days divided into visiting the Mangalore beach and trying the water sports, visiting the Mangaladevi Temple, Butterfly Park, Sultan Battery Fort, Milagres and St Aloysius Churches, eating Mangalorean sea food at Gajalee. In Gokarna you can keep 1 day aside to do a day tour to Yana caves and Mirjan Fort and. Another day you can do beach hopping from Om Beach, Gokarna Main Beach, Kudle Beach with Kudle Beach being the most commercial one. You will get to enjoy food and drinks at shacks and water sports at Kudle Beach. If you are religious and spiritual then you may want to visit the Mahabaleshwar Temple near Gokarna Main Beach. Avoid swimming or bathing at Gokarna Main Beach because it is is filled with jelly fish by the shore. If you are a fish eater definitely try Open House Fishland. Even Chez Christophe Cafe on Gokarna Main Beach serves good continental food. You may also want to hike from Belekan Beach to Paradise Beach and ahead to Om Beach, Kudle Beach incase you are Interested in trekking and hiking. These are all the To Dos. Depending on your interests you will have to divide time and choose
MANGALORE You could start with Mangala Devi temple visit
Explore butterfly park
See what is Light house hill garden is like
Peep into church history of Mangalore
Be with nature in Pilikula Nisarga
Soak your foot in Panambur beach, Someshwar beach and try some authentic seafood in Gajalee. GOKARNA
You can start with Mahabaleshwar temple
Do a banana boat ride
Try beach yoga
See the sunset of Kudle beach
Do camping at Dandeli forest
River raft See Mirijan fort and visit Yana if u hv time.