Bedroom rugs used to mean one thin rectangle under the bed frame, barely peeking out on either side, the kind of thing that came free with a mattress delivery. Lately people are layering them, sizing them up, treating the floor like it matters as much as the walls. I think that's a real improvement. Stepping onto something soft at six in the morning, before the heat's even kicked in, changes how the whole room feels.
In an ordinary bedroom, a rug has to get along with a lot. It sits under or around the bed, usually near a dresser, sometimes a reading chair in the corner if you're lucky enough to have the space. It needs to read as part of the room rather than a separate decision, so I think about what's already fixed and permanent, the floor tone, the curtains, maybe a headboard, and let the rug respond to those rather than compete with them.
If you've got nothing on the floor right now, start with one large rug that extends well past the sides and foot of the bed, not a pair of small mats that just frame the nightstands. A single generous rug makes a room feel finished in a way two scraps never quite do, and it's more forgiving if your furniture arrangement shifts later.
The difference between a rug that holds up and one that looks tired after a year usually comes down to the pile and the backing. Cheaper ones use a thin, flat weave that packs down fast and starts looking matted within months, especially where feet land every morning in the same two spots. A better one has some actual density to the pile, a backing that doesn't crack or peel, and edges that are properly finished rather than fraying the first time you vacuum it. Pick one up if you can. Weight tells you most of what you need to know.
For color, I'd steer toward something a shade or two off from your walls rather than matching them exactly, since a rug that disappears into the floor can make the room feel smaller instead of calmer. Soft neutrals, warm grays, muted clay tones, these all shift nicely between the flat light of morning and the lower, yellower light of lamps at night. Bold patterns can work but they show wear and stains faster, and a bedroom is where you really don't want to be thinking about stains.
If I were starting from nothing, I'd go with a warm, mid toned neutral. Easy with wood floors, easy with most bedding, and it won't fight you later when you change your mind about everything else in the room.