Jeans and t shirts year round, except during the week at work where I wear uniforms. In colder weather I wear hoodies or flannel shirts, if its hot out I wear tank tops and sometimes jean shorts. I prefer white, gray, navy or black shirts and I tend to avoid anything with graphics or screen printing since I feel like a walking advertisement and don't want to be noticed.
In fairness minimalism can be a hard concept to wrap your mind around and it probably means different things to different people.