picture has certain points which involuntarily draw our attention, i.e. the so-called visual centers. And at the same time it is absolutely unimportant what format the picture is in - horizontal or vertical. We are obliged to make use of one of the fundamental principles of composition - the Rule of Thirds. The essence of this rule consists in placing the main object or some other interesting objects of the shot into certain points. These points can be easily identified if you divide the shot into three equal parts with horizontal and vertical lines. The intersection of these lines defines the position of the visual centers of the image. Practically any object lying on the intersection of these lines is sure to attract the viewer's attention. If you are taking a photograph of the landscape, you shouldn't draw the skyline in the middle of the frame because this will make the plot lack action. If you are taking a photograph of the sunset or dawn, you may lower the skyline so as to place it to the lowest third of the shot, i.e. the sky will dominate occupying 2/3 of the frame. This will enable you to convey the expressive shades of the sky to the maximum. And vice versa, if you want, for example, to show the beauty of the landscape, give the sky only the upper third of the shot.
In portrait photography the most important element is the person's eyes. Always leave some free space along the direction of the glance, so as the glance doesn't set against the frame edge. The portrait composition can be more spectacular if you combine the human subject's eye with one of the points of the golden section ("golden" rules of composition). A slight tilt of the head or a good arrangement of the human subject's hands may put some action into the portrait photo. After all, hands are said to be the person's "second face", and so they should be given special attention in the composition construction of the image.
But a good portrait photograph much depends on the well-chosen background. Always draw your attention to what there is behind your human subject's back. Sometimes in the photograph there is a lamppost, a tree, a branch etc. behind the head. The best way out in the majority of cases is a plain softened background. The viewer should look at the human subject whereas a multi-colored distracting the attention background can spoil the impression and can considerably reduce the aesthetic perception of the photo. I wouldn't recommend using a patterned carpet, wallpapers of quaint colors or multicolored curtains as a background.
When taking a portrait photo out-of-doors the most common mistake is when the human subject is placed in the shadow while the background is detailed and well-lit. No doubt, the photo will be poor. The background should emphasize, set off your human subject, i.e. it ought to be less strongly lit or the foreground and the background ought to be