All above suggestions are good ones ...
Suggestions:
1. Avoid traffic jams, roadworks, schools, etc with SatNav/GPS and
TMC. Program economical routes into SatNav.
2. Plan your routes before you set off.
3. Go lightweight - remove door panels, carpets, roof panels, fill
10% of window washer
4. go manual transmission
5. go diesel
6. go hybrid - Toyota Prius
7. know where speed cameras are, slow down and speed up correctly,
use Road Angel 2.