Are you working out consumption yourself or just going by the onboard computer? the latter isnt that accurate.
In general, the best tips would be:
Check tyre pressures and inflate to manufacturer recommendations
Avoid short car journeys
Avoid revving a cold engine hard
Anticipate braking early rather than later, doing this saves energy and doesnt require you to accelerate back up as much.
Avoid using air-con when not necessarily required.
Using premium fuel I find slightly improves throttle response but also seems to get slightly better consumption.
3000 revs seems a little high for fuel saving, try 2500 instead.
Anyway, hello? You're driving an Alfa! Don't worry about fuel consumption too much, just enjoy the car
On that note, minor niggles aside, touch wood, my alfa has been the most reliable car i've had and although it costs more to insure, tax and for fuel, everytime I look at it or drive it, it puts a huge smile on my face!