Wear comfortable business attire. Dress appropriately for cooler temperatures. Turn off any lights that are not needed, especially in unused offices and conference rooms. Turn down the remaining lighting levels if you can. Turn off your computer if you are out of the office for more than a few minutes.
Some computers have a low power stand-by mode.
Check to see if your computer is set for it. If a Stage 3 is imminent, back up your computer and don't forget to frequently save what you are working on, to be ready if the power goes off. What to do at Home Turn the thermostat down to 68 degrees or below. When practical, reduce setting to 55 degrees or less before retiring or when away for the day. Where practical, avoid running large appliances.