In composition, if you can spot opportunities to use shapes and curves, your portraits will benefit.
S-curves in particular are pleasing, like the gentle curve of the background beach coastline here on Toronto Island during the model shoot a week ago, last Monday:
The trees too provide a useful counterpoint to the lovely model.
Now, not that I want to compare my work to that of great artists, but does that background remind you of something?
It does me. No coincidence of course:I recognised the possibility of the nice background because I have been trained to see it by being exposed to great art.
Which goes to show that the way we react to composition has not changed much in the last few centuries. If you want to learn about composition, go visit a museum.