here are some ideas for colour and design,for your little boys room

and a couple more hope these help! its nice to make his room interesting and calm! Whoops doubled up on that one!

Decide if you want a theme or not. Longer life to the design without.
He needs a soft area carpet. I suggest filling the room as much as possible to make it look bigger. You might consider a color from the carpet and stripe the walls approx 6" horizontal with a soft white. Bold but fun. Black and white pics of you son can hang on walls ...ie tying in the black bench. I like blue but suggest to stay away from a bright baby blue. More mature blue will be easier to grow with.

Any baby pictures you can hang on the walls ?

thanks everybody for your ideas, they all look nice.