Wonder is seeing the ordinary before your brain has time to rename it ordinary.

There is a brief window between perceiving something and filing it. In that gap the thing is just itself: the light on a wall, a face, the sound of rain. Then the label arrives and the experience is replaced by the category, and you move on having seen almost nothing. Wonder mostly consists of staying in the gap slightly longer.

Practice delaying the naming for a few seconds. Look at something familiar without immediately deciding what it is. This is a small and slightly strange exercise, and it is more or less the whole technique, available at any moment and requiring nothing.