green wall with black and white photos framed in black...I would add some random things framed, not just photos. Fabric, postcards, train tickets, for instance...
Perhaps the easiest way to create a wall of inspiration is to frame the pictures that inspire you most. These may be pictures of people you know, famous people you admire or places that inspire you. I like this setup where the desk faces away from the inspiration wall so that you aren't distracted by it but can easily turn around to gather inspiration from it.