Turn off all appliances (lights, fans, TV) in empty rooms and when not in use.
Use only energy-efficient light bulbs. LED bulbs are even lower consumption than CFL for the same amount of light.
Ceiling fans move more air than standing fans so prefer ceiling fans for rooms with more people and standing fans for use targeted at one person.
Open windows where possible for better cross-ventilation and natural cooling.
Minimize opening refrigerator doors to keep the cool in.
Upgrade appliances when possible. In particular, newer refrigerators are more efficient and have better seals. Use only LED TVs if possible.
Request an in-person energy audit and find out how to get more from your solar/inverter system.