What color should I paint my daughters room

We moved to a new house and I let my daughters choose the colors of their bedrooms. My youngest daughter who was in 4th grad at the time, had chosen to get a purple carpet, an orange ceiling, two orange walls opposite of each other and the same in purple. Now she's older and doesn't like it anymore but she wants to keep the purple carpet and two opposite purple walls. I'm going to paint the ceiling white, but how should she paint the two opposite orange walls? If she uses wallpaper for both what kind of designs should she do?

I did different wall paper around the world so I'd have new York then Paris then London and Greece and Rome

She should put a primer on the walls you can go to the paint shop and consult them on which to use. Source: Painter knowledge