You might find 76ºF is good sometimes, while other times 68ºF is more realistic. The best way to regulate temperature is to use a timer.
There are a few things you should be doing regularly to make sure your A/C runs efficiently and lasts for years to come.
Try adding essential oil or aromatherapy oil to your air filter. When you turn on your AC, your home will be filled with a fresh scent all day long.