My room got redecortated about a year ago to have a room which matches my age. So if you are designing your room here are some tips.
Two colours look really good together. I have matching colours but constrasting colours give the room a bold, modern feel.
Matching colours: cream and purple
Pink and green
Orange and purple
Red and yellow.
If you want crazy patterns on your furniture I would go for crisp, white walls.
Also wallpaper looks pretty cool if you have one wall covered in it.
Plan a mood board of all the swatches that you want
Make sure it matches!