I always choose a method to fuel efficiency
I make my daily used road route
i.e. if I wanna go to my office there is four ways to destination
I calculated once from four ways which near to destination then I go to my office from that selected nearby route
I can save more fuel from this method
second is always close the windows because due to high pressure of air your car will push opposite side from air so if you closed you will get the better milage
in traffic avoid gear shifting continiuosly
on signal turn your car into neutral, press hand break and remove your foot from clutch
this minor disciplines can save your fuel.