For me one thing is a clean desk. When I worked my 9 to 5, I took time to clean and clear my desk every day. Now I don't, but it is *much* better than it used to be.
I have some favorite things on my desk, a glass cat, a porcelain angel and a heart-shaped glass paperweight. My desk faces an open door (feng shui) am looking for a picture or wall hanging with mountains.
I have way too many books, but am donating a lot of them to my library for our annual book sale.