This is the simplest, most common way to save electricity, and it really works. Start paying attention to how many lights are on in your house at a given time.
Turn off the lights
Be mindful of how many lights you really need to be using at once. When you leave a room, make a habit of turning off the lights, every single time. Use light bulbs which don’t need to “warm up” for areas that have lights which are used for short periods of time. This information should be written on the bulb’s packaging.