Like you, I have a separate space that I call my studio that is my home office. I have a separate computer, separate phone line and most importantly, a separate mindset when I’m at my desk working. I have to also be showered, shaved and dressed for work. I may dress casually, for example, shorts and a polo during the summer, but I always have to have shoes or other footwear on. Being barefooted puts me in a carefree mood, having some sort of shoes of my feet helps me find my productive mindset. Shaving everyday also makes me feel less scrubby and more focused.
I think many folks that work from home full-time have little quirks like that.