- The Visual Triangle;
- The Rule of Thirds; and,
- The Rule of Odds.
To use the rule of thirds you need to imagine the grid on your layout and work from these points and lines. Which point, or line, you place your subject on does matter. While any of the points/lines will add emphasis to your subject, some are stronger than others.
When an object is alone in an image, the strongest position is the left hand line. An exception to this is for cultures where information is read right to left, in those cases the right hand line will be strongest.