When my sister leaves to go to college this fall, I'm going to make some room arrangements. ?

The room is small and has a queen bed and a twin bed. There is also a big dresser and a tall shelf. I would like to move things around to make the room look bigger but still have the twin bed for her when she comes on breaks. How should I arrange the room with what on which wall. Or should one o lf these items be taken out; but I'm keeping the queen bed in.