Two of the many elements that separate a good portrait from a happy snappy are design and composition. A portrait will be composed so that the viewers eye comes in to the scene and goes to the subject then has a place to exit. In essence the image tells a story. Understanding and applying some basic rules will really make a difference.
For example when creating portraits on the beach its important not to cut the subject with the horizon line. Photographs have more impact when the subject is placed in the left third or right not in the center. Keeping the horizon line in the bottom third or top third is also a good idea as it draws the eye into and out of the frame.
Here is what happens if you put a horizon line in the subjects body.

No ladder availabe
While the horizon line is high in the overall composition, the waterline cutting through the mothers head is less than ideal. Having a ladder would have helped me achieve a higher angle and keep her head under the water line.
Here is a portrait that keeps the families heads under the horizon. I order to do this I had to stand on a step ladder.

Family portrait with heads uder the horizon line
Notice how the reflections in the portrait serve as lines of interest to draw your eyes into the family.
Have fun out there!
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