You can install control mechanisms and being aware of how you use your lighting.

Turn lights out when not in the room, regardless of how long you are out.

Always keep control of how many lights you have on.

Always place switches at top and bottom of stairs so that they are easy to reach.

Use a light sensor and controlled timer

There are mainly two types of energy saving light bulbs are available in the UK. Compact Fluorescent Lamps (CFLs) and Light Emitting Diodes (LEDs). 

CFLs are a efficient option for most general lighting needs. Replacing a old bulb with a CFL of the same light will save you about £3.5 per year, or £60 for the lifetime of the light bulb.

LEDs are more expensive to to start with, but they are much more efficient than CFLs and will save you more money in the long run.