Learn to read traffic patterns by anticipating traffic light changes so that braking and accelerating are minimised. Heavy braking and flooring the accelerator both waste fuel. Try to use just the first quarter of the accelerator movement. For the best results under normal driving conditions, try to keep the accelerator pressure steady. Change up quickly and save.
Lower gears use an excessive amount of fuel.
Change up as quickly as circumstances permit. Skip a gear, say first to third, if you can. Close your windows. Use your handbrake on hills. Never ride the clutch to hold your car on an incline.