Once you’ve studied the rules of lighting and composition, you’ll never look at the world the same way again. It could be as simple as the way sunlight sparkles in a dewdrop on a leaf or the way your friend’s hat frames her face and draws attention to her eyes.
Ideally you’ll want to have your camera ready for such opportunities. If not, try to figure out what exactly appeals to you about the scene. The more you do this, the more you’ll begin to appreciate everything around you, and your pictures will be better for it.
So there you go. That’s your assignment for the week.