How I can decorate a small room without making it look messy?

My room is small. I have a dark wood bed queen smooth dark wood buffet. My walls are a soft blue and gray, navy and I have curtains. Besides, my closet doors were removed and replaced by blue curtains marine long, open space. However, I do love collages, and I have them all in my room, but I think it is time to take them and replace them with a couple of shelves with frames in them. But space still seems quite small, and I feel suffocated when I'm here. I am a worker High Schooler, so I use my room to do homework, etc but do not even have an office. What color comforter should I get to make the room look bigger? I have white sheets and colors accent (solid color), but I'm not sure .. It always seems like there are too many tricks for this little space. HELP!

you have a lot of dark things in your room. I want to keep it that more and more light. You do not get white, just the color is light. Especially its walls.

I love clouds!

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