Sit quietly with your eyes closed, pick a room in your house you are not in but know very well, and try to picture it in your mind in painstaking detail. 

Locate and identify all the objects in it, decorations, familiar patterns of light and shadow, smells, sounds. Disregard nothing, from the color of the carpet to the cobwebs in the corner or the whoosh of the air conditioning.

Take a moment to write a detailed description of what you envisioned and then go to the room and check your description against reality.

When you shed the obvious details our memory stores unconsciously, the subtle ones you ignored start jumping at you: the crack in the wall, the metallic hum in the vents, a pencil cup that’s out of place, small tchotchkes and colors you got wrong.

This exercise strengthens the power of visualization and trains attention to details.