Annie Hall’s newlywed clients had just one requirement for the small bedroom in their new South End condo: a king-sized bed.

If there’s only one occupant of the bed, that king can ... loft beds as small as twin size, so as long as you have the ceiling height to make this work comfortably. If the bedroom has a closet ...

as can a small bed in a huge room. A ratio of around 1:3 between bed and bedroom is sometimes said to look best, but that can be difficult in practice. Following this advice would mean, for instance, ...