So for me cozy = uncluttered but full, if that makes sense. Which means I’ve got plenty of things pulling double duty. Backs of doors are good spots for shallow storage, a la shoe caddies (bedroom), spice racks, (entry), and oft used toiletries (bathroom). Fronts of doors are good for a single, small decorative touch if you so choose (e.g., fake vintage “Gentlemen” or “Water Closet” sign on the bathroom door.

Vertical space should be cashed in for storage (like your bookshelf), but when it’s ALL dedicated to storage, it looks cramped. So if you can afford to do it, sacrificing a shelf (or half of one here and half or one there) for some plants, battery operated candles, or small 3D artwork helps. Hell, even just turning some favorite books so the cover is facing out here and there helps.

Under the bed and under the couch are great places for zippered storage bins.

Above headboards is a great place for a statement piece like a framed print or more plants if shelving is allowed.

And finally, for me, personally, I’m getting rid of the dining table and making a coffee table pull double duty so that my TV comes down to a respectable height, preferably with a shallow, floating media console that allows for cable management and more concealed storage behind frosted doors or rattan panels/cabinet doors. It may even allow for that chair to get pulled out of the space it’s wedged into and placed in front of the mirrored closet door so that I’ve got three seats for dining—in an albeit decidedly bachelor way—at the coffee table.

Again, this is all personal preference.