Observe, I do this a lot. No matter where am at, I just like watching what around me. It even more interesting when you are out in public and just observing people. The most common thing I’ll see are people glue to their cell phone. Looking down at their screen and not even being aware of their surroundings. The most recent thing I’ve notice about people are what they wear in public. I really believe that some females leave their home without looking in the mirror. Am all for dressing comfortably in hot weather, but you should make sure your not showing to much. Especially if you are going to the gym.
You can also record what you observe either by writing or like me and others through photography or drawing. I recently started doing urban sketching. Taking a sketchbook with me and just pick a spot in the downtown area and draw what I see. You can do this when visiting your favorite coffee shop.