
Whenever you take pictures, try to imagine how it might look, divided into sections - this generally makes a more pleasing and technically 'better' photograph. You don't have to worry about Rules - just think of the subject in your mind's eye and think if it might look better if you step a yard to the left/right, or if you point the camera up or down slightly. Create the picture in your head before you press the shutter button.
Here, the pleasing effect of the Rule of Thirds is at play again - sections of the image taking up one-third of the frame and also the 3 different sections of the seascape making a visually nice contrast and again leading the eye into the picture.