Learning to attend to visual contexts more closely than ordinary "looking" requires, and thereby to see things that otherwise might not be seen.
The thing about "Observe" is that, again I need to refer to David Perkins, a lot people think, "What's the big deal, so you look and you see." But the truth is that as you become more sophisticated in your artistic mind, you develop the skills and attitudes that give looking time, that cause you to take different perspectives, to look for certain variations, to compare and contrast. There are all sorts of ways in which artists observe and develop their capacity to observe, to see. They play with metaphors. They play with all sorts of interpretations. All those things help them to see. So a lot of times artists go back and forth between "Envision" and "Observe" – it's another creative tension. Think of "Envision" as the seeing you do in your head and "Observing" as the seeing that you do with your eyes. So, if I am trying to draw a figure as an observational drawing, and my teacher tells me to see the figure as geometry, I'm observing, but I'm also envisioning the figure as something that it's not. So there's a lovely tension between "Envision" and "Observe." (From http://www.everyarteverychild.org/)