Besides aligning the landscape or items within your viewfinder along lines of thirds, it's equally important to look for leading lines or curves to form a S shape to create a more dynamic image.
These principles can be applied to making any visual image not just a high end SLR camera, but even a camera phone and most importantly before these creative tools were invented it's been long established as a compositional technique in painting's and sculpture.
The images below despite being from two separate eras made almost five hundred years apart, are excellent examples of using an S curve as a crucial part of the viewers enjoyment. Besides being completely different mediums one a two dimensional photograph the other a three dimensional marble sculpture the principles of leading the viewers eye from lower left to upper right in a S shape are similar.
|Photo by Cartier Bresson (1950's)|
|Apollo and Daphne by Bernini (1625)|
One of the advantages of three dimensional sculpture over a photograph, is the shape of an S can be maintained from different angles, this also demonstrates the genius of Bernini who could sculpt this with primitive chisels out of square blocks of marble.
|S Curve on the image plane.|
So the next time your about to take a photo of a scene or moment that interests you. Look, before you click the shutter for something that could form an S or leading line in the scene, the obvious being a path or road but people or any sort of items can be used to lead the eye in the final image, I've even seen photographers use tracks in sand or snow to good effect.
|Train British Colombia, Canada.|
Also the three main colours in the photo are the three primary colours in the photographic printing spectrum Red Green and Blue (RGB). Although it was just luck that the train was red.
Try it yourself on any camera or Iphone, think outside the box and once you know the rules break them.
I like to think of it as the eye going on a journey.