It will come with practice...............get your instructor to tell you how he does it..........more than likely he has spent many hours over the same area.
One town can look very similar to another so I always look for line features first..........Rivers, Railways, major roads, then distinctive features like power stations, lakes and large woods . keep in mind that the view can change very dramatically with different visibility, time of day, and seasons throughout the year.
Rgds cirrus01