Tip1 : Divide your trip to 2 parts . South goa ( for quiet time with less folks and attractions ) and North Goa ( for lots of folks, shopping and attractions ) ...
Tip2 : Spend a day in south Goa and then take a trip to Palolim beach( see butterfly beach and dolphins etc ) and if possible then have dinner James Cafe and beach hut
Tip3 : Go for water sports in north goa local beaches and don't get trapped to other locations otherwise you may waste both time and money
Tip4 : Spend an evening on boat cruise at Mandavi river in Panji
Tip5 : Spend an evening at Bagha beach for dance,drink and dinner