I want to redo my room?

My mom promised me i could redo my room in the 8th grade. Im in 8th grade and she said i could redo it, but not the way i want it. right now my walls are pink, ive had it since 3ed grade. My room is small and is crowded, i have a bed, dresser, hutch, desk and a side table. I want to get ride of the desk but my mom says we dont have the room. I dont use the desk and hate it. My mom forced me to move the desk form the guest room to my room. I want to completly redo it and paint it purple and sponge paint it with a darker purple. got any sugestions on what to do to convince my mom to do what i want and some ideas for my room?