Don’t overheat your thermostat. If your thermostat is mounted where it can receive direct sunlight, or is exposed to local heat from a light or an appliance, your air conditioning might be running too often and using excess energy because of it. Likewise, don’t overcool your thermostat. If it’s right near the outflow from the air conditioner, it may sense a lower temperature earlier, and cut off before the room is cool.
Increase the humidity in the room. In hot dry climates, adding moisture to the air can help to cool a house, so running a humidifier, or having a ‘swamp cooler’ installed, can be a low-energy air conditioning improvement in some regions.