Conduct activities that require hot water early in the morning or later at night. This will prevent heat being added to your home during the times of day that temperature is the highest.
Use cold water for washing clothes, dishes, and floors.
Use compact fluorescent light bulbs rather than incandescent light bulbs. Fluorescent light bulbs use 75% less energy than incandescent light bulbs. They also produce 75% less heat. This will reduce the amount you pay for lighting and also reduce the amount you pay for air conditioning.
Turn off lights and all appliances when not in use.
Keep blinds shut as much as possible. This will prevent the sun warming your home.
Use ceiling fans and portable fans whether you have air conditioning or not. This keeps the air circulating and the temperature cooler.
Turn up the thermostat when leaving your home and during cooler times of the day.
Wrap your water heater and the pipes that are attached. This reduces heat significantly. Wraps are very affordable and they save you money while in use.
Change or clean your air conditioner filter regularly. Dirty filters restrict air flow and reduce efficiency. You should do this at least once a month.