When I go to a new city, I follow my satnav device for the first few days, then start altering my route -- deliberately missing turns, or starting out in a diff

When I go to a new city, I follow my satnav device for the first few days, then start altering my route -- deliberately missing turns, or starting out in a different direction, to learn where it takes me as a result of those changes. I'll study the map before I depart, and plan which turns to blow, and predict what reroute I think it'll give me. After a week or two of this assisted learning, I tend to have a pretty good base map in my head, so I start doing without. I'll leave the device face-down on the passenger seat, not giving me any hints, but still tracking my location and there for a quick peek if I get turned around. After a few days of this I can typically do away with it entirely.