(Due to Kim's busy schedule this week I'm writing this one from my own experience as an artist - Cheryl)
With all the visual stimulation we get from the moment we wake up in the morning until we close our eyes to sleep at night, you would think that your eyes get plenty of exercise. Unfortunately, they may not be getting the kind of exercise that helps you as an artist. As a matter of fact, our eyes sometimes become desensitized to the subtle beauty that is around us all the time simply because there is too much too take in.
In the same way that information overload can make us want to stop reading or listening, visual overload can cause us to subconsciously stop looking. This state of being could be called artist block, when we lose inspiration about what to draw, paint or create. You might think the solution is to close your eyes, but it's not. On the contrary, taking some focused time to observe more carefully can give you quite a lot of inspiration.
As a photographer I found myself more naturally focused on composition, but I would do similar exercises to train my eyes to notice a good composition quickly. By holding my thumbs & fingers in the shape of a rectangle I would observe the possibilities for compositions all around me. Sometimes I would use a small pre-cut mat as a sort of window to frame my views of the world. Even while carrying a camera sometimes I would just practice composing in the viewfinder without taking the photograph. This kind of practice allows the subconscious to take over the work of composing while you consciously note the other factors like light & shadow, color, focus, etc.
It becomes a habit after awhile, these exercises, so that every moment becomes an opportunity to notice shape, form, texture, line, pattern & composition. In this way the world becomes filled with artistic inspiration and never ending possibilities. Every person is unique and feels inspired by different things. For some people going to art shows or museums will get their creative juices flowing, for others it is nature, and for some it's taking classes. However all artists need training & practice as we strive to improve our skills. I hope these ideas stimulate your own thoughts or help you find new methods for artistic practice.