Another old-fashioned practice I maintain is carrying a notebook, a small one I keep in my shirt pocket and never leave the house without. In it I register all the little things that strike me, not in great detail but just quickly. The following morning I'll review what I jotted down and look for the most meaningful moment in the previous day, the one in which I felt truly present.
It's worth mentioning that this is my edit. It wasn't easy revisiting what are now 156 volumes of my diary.