It can be very painful to try to get a tan in a week, or two, or three weeks. And I was not about to try. When I go to a beach area for a picnic and swimming, I want lots of shade.
A nice natural area is along the highway into Lahaina at Mile Marker 14 (+or- a mile in either direction). There are lots of trees, almost down to the water, which provide great places to hide from the sun and other people. The ocean is always calm and there are usually lots of fish to see in the sand channels between the coral heads.