Start with the walks you actually take. A shoe for paved errands may need a different balance of flexibility and protection than one for long days on mixed paths. Consider the surface, weather, distance, and whether you carry a bag. A comfortable shoe is one that suits your routine, not simply one with the thickest cushioning.
Check that the heel feels stable without rubbing and that the forefoot bends naturally as you step. The shoe should hold your foot securely without squeezing it. Leave enough space for your toes, especially if you walk for extended periods and your feet tend to feel fuller later in the day.
Try walking at your normal pace rather than judging the pair only while standing still. Notice how the cushioning feels after several minutes, whether the sole feels awkwardly stiff, and whether your foot shifts inside. If you use supportive inserts, bring them along to check that they fit comfortably without crowding the shoe.
Replace shoes when wear changes how they feel or function, rather than following a fixed calendar. Uneven wear, damaged cushioning, or a loose upper can be useful clues. Keep in mind that wear patterns alone do not diagnose a gait problem. Choose comfort and fit first, and seek professional advice if walking regularly causes pain.