Sensations of feet connecting with the ground, and the feeling of the body moving through space from one point to the next. The flow of air all around, touch of it on skin and clothes. Eyes half-closed, with a soft gaze. Mind centered with the body and the experience of walking. But aware of what is happening in peripheral awareness. Knowing where I am. What I am doing.
With walking there is that sense of working through stuff. Perhaps it is the forward motion of walking which brings a feeling of making progress, pushing through it, the sensations of movement and change.
I can get into a flow sometimes when walking. The self disappears and everything becomes energy. There's a feeling of oneness, absorption, a blissful feeling of freedom from the unpleasant feelings that come from longing, aversion and conceit.
Sometimes I stop and look at the sky. And feel a sense of awe, that there is even such a thing as sky. The clouds pass by over the blue background, and the cool breeze feels pleasant, the plants swaying, all of it is changing.