We had similarly sized small children's bedrooms to stage. Our stager recommended we remove ALL the furniture, except for the bed. He then re-positioned the bed so it wasn't right against a wall. Had to play around with this part, and the bed was ultimately placed differently in each room, as the rooms had different layouts despite similar dimensions.

Since we'd removed the nightstand and table lamp, he had us add a floor lamp. Normally he's against floor lamps for staging, but it worked for these rooms.

We repainted the whole thing a light neutral color (like white, or a light beige). I'd repaint your trim white as well. Left the carpet on the floor because the floor wasn't that great. Kept the bed nicely made, with a stuffed animal or two on it.

Removed all the artwork and mirrors from the walls, but did leave a few kids' trophies and awards as a reminder our home was in a top-rated school district. (We had wide window ledges to place these on).

Cleared out the closets completely. In our case, the closets were generously sized walk-ins. Kept the closet door open and closet light on during showings. Kept the window shades wide open as well.

The two rooms looked much more spacious when all they had was a bed in them!

Of course this worked for us as our kids had already moved out.....