Originally Answered: How should I design my room? 13 year old girl?
You have four colours, but your design for the room needs to be based on how you will use the room.
Since your room will be a respite from the rest of your life, but also where you do homework, dress, socialise, and so on, you want a room that is cheerful and bright without being overwhelming.
To accomplish this, and to have a room that's easy to redesign in a few years when your tastes change, put the baby blue on the walls. It will open up the room, making it bright and easy on the eyes, something the other colours wouldn't do on a huge surface. You can do the trim in brown, which will look calm and sophisticated. Then, add some brightness with pink curtains, a pink and blue lampshade, and some brown, pink,and green cushions. Get some baby blue trim for some things and you'll tie it all together. Remember- base colour first, the most neutral and easy on the eyes. Trim in a colour that matches well. Then, add the brightness, so the eyes are drawn to it- the pink and green will stand out and look cheerful and bright without being busy or overwhelming, and the room can look energetic and exciting without being too visually "cluttered" for your bad days.
Think pillows, think pictures, think curtains and throws, they'll all add the splashes of colour you want.
Later, you can take a colour, and paint right over that baby blue with a pattern, to make your room different again, or the light blue will be easy to cover with another colour entirely. Or you can take out the hot pink and green throws and add sea greens and deep blues to have a soothing, sea-side like room. It's easy to change that way, and you can make it exactly what you want right now.