What's the actual act of "storing" something at a locus?

Turn the item into a concrete image and stage a little scene where that image interacts with the locus.

Two moves: (1) make it a picture (an abstract fact → a concrete, visual symbol), and (2) plant it in the place so the image and the locus physically collide. Don't just set a "moon" politely on the sofa — have the moon crush the sofa, or the sofa swallow the moon. On recall you arrive at the sofa and the collision replays the image. The locus is the hook; the interaction is what makes the image hang on it.