(via How To Control Flow Within Your Web Designs)

Let’s start with the idea of creating a hierarchy of focal points with an entry point sitting at the top of the hierarchy. Consider Kandinsky’s Composition VIII seen below. The large black circle in the upper left is the entry point into the painting. It’s the first thing you notice. It’s larger and darker than anything else on the page. It holds more visual weight than any other element in the painting.

Your eye possibly moved on to the circle in the lower left and from there started following some of the other circles along the bottom. These smaller circles carry less weight than the dark one we started at, but they still carry more weight than many of the individual elements in the painting. They pull you toward them and once there your eye rests momentarily before moving on to the next.
Lines and curves are another way to lead the eye. Look at the green circle in the lower right of the painting. There are a number of lines near it that pull your eye up through the painting. The long line to the right of the circle meets with other linear shapes that are parallel in direction. There’s a good chance they pull your eye to the top. Maybe to the point of the triangle.
To the left of the triangle near the top are two curved lines with some perspective. They lead your eye to the light blue mass between the triangle and our entry point circle. In fact the more you move around the painting you can find lines and curves that guide your eye from one element to the next.
I mentioned that repetition can create flow. We see repetition in the circular shapes and in blue, yellow, and green color. The repetition creates implied lines and curves between elements for your eye to follow.
One last point before we leave the painting. Another thing I mentioned above is the idea of keeping people inside your composition. Look anywhere along the edges of the painting and you’ll find something that leads your eye back into the painting. Kandinsky does a wonderful job of keeping us inside and moving from one area of the painting to the next. It’s a great example of compositional flow.